When a Homicide investigation into the disappearance of a teenage babysitter fails to reveal any useful evidence, Church and Angie go undercover to infiltrate a sinister criminal family.

Someone is looking to hire a hitman, so Church goes undercover. Surprisingly, his client is a woman who claims that her husband is trying to kill her. She wants him dead before he succeeds.

A policeman has been shot. Undercover is called upon to infiltrate a suspected Romanian gang, but they don't deal with outsiders. Rocca must rely on an ex-undercover operative who could potentially jeopardize the job and the unit.

Undercover is called in to find a serial killer. When Angie's cover is blown, Kaye becomes her replacement. Her first solo job is going well until all contact with her is lost and she vanishes.

Following Kay's disappearance, the Unit goes into damage control, scrutinizing the surveillance footage and following up on the few leads they have - a process that provides an unexpected suspect.

Whilst undercover, Church is employed by a brutal mercenary, Cameron Fraser, to assist in the abduction of a young girl. After a botched attempt, Fraser successfully tails Church, putting the security of the unit at risk.

Following the drug-related death of a young clubber, the unit attempts to crack a large scale Ecstasy racket.

MacKenzie is put undercover on the witness protection scheme to befriend a victim of attempted murder because of her connections with a leading politician who is suspected of corruption.

While taking part in a buy/bust, Church and his dealer inadvertently get caught up in a siege instigated by three teenage criminals.

The Professional Integrity Unit investigates undercover over claims of corrupt handling. After evidence leads to Rocca's suspension, the unit wants to know what's going on.

Church is forced to drop his longtime informant, Benny. Benny is outraged, but as a last hurrah, he gives Church information about a planned armoured van robbery.

Working undercover with bikies, Church sets up a buy/bust which turns sour after Stone is bashed and falls into a coma. Emotions run high as Church is forced to remain undercover.

After Stone is nearly shot during a meeting with a dealer, Mac is worried about Stone's well-being when an informant helps Stone penetrate a gun dealing ring.

The Unit goes undercover to locate a charismatic prison escapee, Kane, who accuses the police of wanting him dead rather than recaptured.

Stone and Angie go undercover to infiltrate "Mother Earth," a radical environmental group suspected of stealing explosives. Church is put in prison to befriend Aaron Feilder, the psychopathic leader of the group.

Church encounters Stone as part of the environmental extremist group. Stone wants to report to the unit but Church, driven by his own agenda, insists that any contact would jeopardise the sting.

Someone is killing prostitutes and when a second woman is found murdered, MacKenzie and Angie go undercover at a brothel.

When Church goes undercover to investigate a murder, he inadvertently ingratiates himself with the Rossis, a criminal family currently the target of an independent inquiry. Church is ordered to remain undercover.

With the help of the unit, Church manages to impress Dino Rossi and weaken the position of his right-hand man, who is resentful of Church being accepted into the ranks.

With Church recruited by the Rossis, Angie goes undercover to investigate one of Dino's contacts. Church is falling in love with Dino's sister, Christina, and may ultimately have to choose between her and the Unit.

While the Unit learns of Church's relationship with Christina, Church is forced to come to terms with Christina's involvement with the family business and refuses to testify against Dino.

Information comes to light that someone is trying to sell Dino details about Church. With his identity revealed, it is a deadly race against time for Church to save his relationship and his life.

Stone and Angie go undercover to investigate the murder of a young Asian woman involved in the X-rated movie business. MacKenzie receives a compromising photograph relating to her former relationship with Church.

The compromising photograph of MacKenzie and Church threatens the security of the entire unit. Church pursues the source of the photos while Angie and Stone push for more information on the Porn Star murderer.

Church works undercover as a safecracker to find out the target of the robbery, discovering that the gang have a one-off, get rich quick scheme.

Rocca finds himself in unfamiliar territory when he goes undercover with Church on a case involving gold smuggling and political intrigue.

The Unit pull off a successful cocaine bust, leaving drug lord, Bryce Forbes, wanting revenge. Acting on information supplied by Forbes' lover, Heather, Stone is sent undercover to infiltrate the drug lord's operation.

MacKenzie goes undercover in a woman's prison. Her target is Nancy, a young woman convicted of murdering her husband, who embezzled millions of dollars in an investment scam. The Unit's aim is to recover the money.

Stone and MacKenzie infiltrate a gang planning to rob and murder a coin dealer. When they lose contact with the Unit, Rocca must second guess their movements.

Church is due to give evidence in court against major crime figure, Dino Rossi, but the Unit discovers someone wants Church silenced before he can testify.

MacKenzie works closely with Maddern, a psychological profiler, to identify a killer who uses the internet to select his victims. With the Unit in full-scale back up, Mac is put undercover as bait.

Working undercover as an ex-army officer, that now supplies illegal explosives, Stone encounters his first girlfriend, Kelly, entangled in a contrabrand arms export scam.

While investigating large scale thefts on the docks, Church accidentally shoots an old mate, Tony. While Church is suspended, the Unit continues to uncover the extent of the shipping robberies.

Church and Angie go undercover to investigate suspected drug importation in the music industry. Church works on the record company manager, while Angie investigates charismatic rock star, Jimi Mercer.

Stone leads a sting on a well known crime family that doesn't quite go to plan as the eldest son, Billy, escapes. Stone and Angie lay low at Stone's family farm, but Billy tracks them down.

When the daughter of a Family Court judge is abducted, Church teams up with Rory, a young Undercover recruit, and together they investigate a group lobbying against the judge.

While investigating a heroin racket, Church encounters his nephew, Matt, who has fallen victim to the needle. Church spends time with Matt, experiencing the emotional, rather than criminal, side of heroin addiction.

Undercover with Angie and Stone, Church investigates a series of strategic truck-hijackings which have turned to murder.

When the husband of a leading Aboriginal activist is car-bombed, Stone and Angie go undercover to investigate SWARM, a radical right-wing group suspected of involvement.

When A.J, one of MacKenzie's informants, finds out that the adoption of his young Vietnamese daughter wasn't strictly legal, Church and MacKenzie uncover a ring of child smugglers.

By using Stone's informant, Rocca plans a dangerous drug operation to land a well known drug heavy. The drug operation is put at risk when Stone's informant goes into labour and Church is left holding the baby.

Church and Mac go undercover to infiltrate a group of high-roller gamblers who conduct illegal gaming sessions. The sting takes a bizarre turn when the gaming session is raided, not by the police, but by robbers.

When Rocca is shot outside his home, Church becomes obsessed with finding the gunman. Mac assumes she will fill in for Rocca so there is friction aplenty as a new boss joins the ranks.

Church meets a new informant, Terry Hanks, who repeatedly delivers big time drug dealers, but when Terry offers to land them 'The Dingo', the biggest and baddest dealer of all, Mac and Church have their doubts.

A sassy new operative arrives at the Unit just as the group go undercover to entrap a gang of teenage thieves. However, a mistake leads to as kidnapping which places everyone in jeopardy.

Church goes undercover into the world of stolen art. When he discovers that the target is abusing his son, Church's repressed memories of his abusive father are triggered and he must grapple with conflicting emotions.

A well planned sting goes horribly wrong when Church infiltrates a criminal gang who are intent on robbing a very large bank.

Angie's assignment is jeopardised with the unexpected arrival of her sister. Mac is faced with a crisis when she discovers that Danni is involved with a suspect.

Danni's future with the unit is on the line when her ex-boyfriend becomes the prime suspect in a horse-doping scam.

Hollister asks Mac for help to capture master bank robber, Marty Stockwell. Hollister wants revenge after Stockwell fatally shot one of his men. Church and Danni go undercover to bring Stockwell to justice.

In court, things go horribly wrong when the Magistrate dismisses the charges against Tony Howarth for shooting Bernie Rocca. Church comes under fire from Internal Affairs after he is accused of using excessive force to obtain a confession.

Church becomes involved in a young boy's life after he catches him trying to steal his car. Meanwhile, Angie goes undercover to expose a dentist accused of malpractice.

Three backpackers are murdered. Stone is sent in to investigate the suspect, Evelyn Leigh but he lets his emotions cloud his judgement - a mistake that could cost him his life.

Mac and Church must infiltrate a neighbourhood residents group who are protesting the acquittal and return to the neighbourhood of a local teacher recently charged with the murder of a young student.

When Church conducts a sting on a bikie gang, a simple gun deal becomes complicated after Church is hired to do a hit.

The undercover Unit face a psychological challenge when an operative loses his identity during a long-term assignment.

Church strikes up an unlikely friendship with a hitman after preventing his attempted suicide. He is drawn into the middle of a heated triangle with no simple solution.

Danni learns the meaning of betrayal when she is forced to use an innocent to solve a murder.

MacKenzie faces a dilemma when Detective Inspector Bill Hollister is revealed as a regular client at an illegal brothel.

Danni and the rest of the team are called in when a well-known career criminal turns Crown witness under unusual circumstances.

MacKenzie's past comes back to haunt her when her adopted brother is released from prison.

While working to exposed and armed robbery ring, Angie is stalked by an obsessed admirer. The stalker not only jeopardises Angie's sting, but threatens the security of the entire unit.

Church must put his career on the line when an old Academy buddy is implicated in a homicide.

A personal favour from Church becomes a case for Undercover when an illegal organ-trading scam is exposed.

The Undercover Unit are assigned to investigate a five-year-old unsolved bank robbery with tragic consequences.

MacKenzie and Angie face an internal Affairs investigation when an informant commits suicide.

The Undercover Unit is called in to investigate when eleven illegal immigrants are found dead inside a shipping container.

Church uses an informant to infiltrate a drug syndicate, with tragic consequences.

Angie goes undercover at a halfway house to obtain evidence against a psychopathic killer.

Church and MacKenzie pose as a married couple experiencing relationship difficulties as they investigate a murder.

Church becomes the prime suspect in a murder investigation when he moonlights as a private investigator.

Church goes undercover in a bikie gang to expose a major amphetamine ring, with unexpected and tragic consequences.

The future of the Undercover Unit looks uncertain when Stone is investigated for the shooting death of biker Chicken Lake.

In the aftermath of Bill Hollister's murder, MacKenzie grieves while Church tries to bring the killer to justice.

Church and Danni pose as foster parents in an unusual operation to capture Australia's Most Wanted Armed Robber.

The Undercover Unit investigates a group of paedophiles who use an internet chat-room to procure their victims.

The Undercovers investigate an extortion attempt against a pharmaceutical company and find themselves at the centre of a long-term feud.

Stone is recruited by an Assistant Commissioner to assassinate the Bomb-maker responsible for Bill Hollister's death.

The Undercover Unit stage an intensive investigation to nail the ex-police officer believed responsible for Bill Hollister's murder.

Danni's cover is blown and her career is threatened when an escaped criminal seeks his revenge.

A case of mistaken identity results in Stone being recruited to assist with a major armed robbery.

Strange guns, UFOs, and piggerists with glass eyes - it's all in a day's work for Church, when his only source of information for a possible murder case is a paranoid schizophrenic.

MacKenzie investigates a Private Detective who specialises in adoption cases, with the secret hope of locating her birth mother.

MacKenzie makes contact with her natural mother and both women become embroiled in an Undercover operation to nail a mastermind armed robber.

The Unit works with an undercover operative from Queensland to defeat a gang of amphetamine dealers responsible for a kidnapping.

Stone is caught in a siege situation at a hospital when an armed robbery goes horribly wrong.

Church's worlds collide when he has to attend his twenty year high-school reunion as part of a drug sting.

As Church, Danni, Stone and Angie focus on a drug sting, MacKenzie is distracted by an invitation to apply for Head of Homicide - which would mean leaving the Undercover Unit.

MacKenzie becomes the victim of a grifter on the eve of her interview for Head of Homicide, while Church's career is threatened when a journalist attempts to expose him.

Angie has to develop a romantic relationship with a murder suspect and then coerce him into becoming an informant.

Danni's determination to go it alone with her pregnancy clouds her professional judgement when she stumbles across an illegal adoption racket.

MacKenzie discovers the grifter who drugged her is linked to a senior colleague - someone who had good reason to want her out of the running for Head of Homicide.

Stone cultivates a live-wire young prostitute named Brittany to get information on a dangerous drug criminal.

When Church is sent under cover to share a cell with a convicted murder, Danni must face the toughest decision of her life alone.

Angie is forced to bend the rules as she attempts to prevent her sister Sam from being arrested on drug importation charges.

Danni has to protect former undercover cop Gary Edgerton and help prepare him for a court case where he is the reluctant key witness.

Stone investigates a woman who may be organising a hit on her husband, while MacKenzie is dealing with hit men of a different kind.

Angie and the rest of the Undercover Unit rally around MacKenzie, risking their jobs in order to prove her innocence.

With Harry Love in a position to make his final move against MacKenzie, she and the other Undercover have to take desperate action.

Angie goes undercover to bust an armed robbery ring but her romance with informant Marty Engle places them both in dangerous territory.

Stone and Church go undercover to investigate a pair of teenage drug manufacturers, with unexpectedly tragic consequences.

Stone is abducted when Undercover fails to bust an international arms dealing ring that is run by lethal ex SAS officers.

When a failed drug bust leaves Undercover with a dead dealer and a high class prostitute holding a couple of bags of cocaine, the Unit undertakes an operation inside a busy brothel.

When an undercover operation causes the death of a young woman, Church and Angie are faced with the dilemma of saving one dangerous criminal from another.

The Unit's attempt to trap a serial killer leaves MacKenzie fighting for her and her best friend's life.

Stone is set to expose a high powered businessman trading cars for heroin when he discovers a young prostitute he has cared for is in danger as a result of his actions.

Church becomes convinced he is being stalked by a man who holds him responsible for the murder of his girlfriend.

When the Unit try to nab a standover man for murder, Angie's relationship with an informant causes a confrontation within the ranks.

The unit seems on shaky ground when Homicide attempt to charge Church with murder, but are devastated when Stone goes beyond the call of duty to save Church.

MacKenzie is faced with a choice between her personal happiness and her successful career when she becomes involved with a charismatic art thief.

Oscar Stone's Killer is brought to trial in a situation of high security. The accused is represented by a high profile criminal barrister, Ingrid Burton.

When Church goes undercover as an armed robber, he is busted by a young cop. Harris is so impressed that he arranges for her to join Undercover for a trial period.

Church's undercover assignment results in the kidnapping of a drug dealer's son. Meanwhile, Chris finds herself on what appears to be a routine surveillance job at a video store.

An undercover attempt to sting a drug distributor results in tragedy, with accusations made against an undercover operative.

Harris sends Chris undercover to infiltrate a violent gang of brothers despite Church's reservations about her inexperience.

A middle-aged woman, Helen, brings a cardboard box into police headquarters claiming it contains a bomb.

Church's hapless pursuit of the coke happy Vidarl crew takes a turn for the worst when most of them turn up dead - victims of a bloody armed robbery.

Church goes undercover on a building site to investigate union corruption and the disappearance of activist Craig Shore.

Church goes undercover on the construction site where Ingrid Burton's client, Steer, was murdered. Church is convinced that Harris is corrupt and goes to extreme lengths to prove it.

Church and Angie continue piecing together links between Conrad, suspected drug kingpin Sting Endquist and known union basher Rick Tyson. Harris suspects Church of corruption.

Harris is clearly losing it and is convinced that his officers are out to get him. In his paranoid state, he decides it's time to do something about Church...kill him.

The cat is well and truly set among the pigeons when Church and Harris are forced to work together determined to catch two small-time dealers.

Church and Harris find themselves under extreme pressure to clear their names after the Police Integrity Unit are tipped off about the duo's possible involvement in a drug trade.

When drug boss Sting Endquist survives an attempt on his life, Church convinces him that the assailant was Stone's killer, Conrad.

Church's determination to find Ingrid, missing for seven days, brings him into conflict with his colleagues.

An undercover operation investigating stolen art reveals black market dealings.

Harris' attempts to teach a mate a lesson in crime and punishment backfire with disastrous consequences.

When Angie is hired as a nurse by two brothers, she's forced to go on a job without back-up.

Chris' future is jeopardised when she's forced to shoot a former squat mate.

The team lose a colleague when a hostage situation erupts at Police Headquarters.

While investigating the murder of a friend, Church loses Angie's Heart to his boss, Luke Harris.

Church and Angie penetrate the liberated world of swinging couples and find that love really is a drug.

Church fakes the murder of a security guard to infiltrate a Jewish crime family.

Chris' relationship with a lesbian clubber turns to tragedy when her lover is suspected of murder.

The unit discover a renegade young detective who has all the qualities to become the new undercover recruit.

Rookie Leo Flynn bites off more than he can chew while investigating a drug war between two rival ice-cream vendors.

Harris takes an impulsive trip to Singapore in an attempt to win Angie's heart and protect her from Internal Affairs.

A young deaf girl arrives at PHQ declaring she's Church's daughter. When Harris uses her to solve a crime, all hell breaks loose.

The undercover unit simultaneously pursues a European war criminal and her drug dealing son.

A sexual indiscretion of Harris' comes back to haunt him when Church is hired to kill him.

Church makes a dangerous call when faced with a conflict of loyalty between Harris and his old boss, Bernie rocca.

Flynn endangers his life and that of his pregnant sister on a deadly assignment with two cop killers.

Chris risks her life to sting a sadistic chef for murder.

Church is hired at a furniture removal company suspected of a drug Courier business.

Masters goes undercover in order to bust a racehorse stealing, coke dealing porn king.

Church goes undercover as a spiritual medium to hoodwink an international gun runner.

Sophie takes Church to lunch with two of the state's biggest criminals. But will the meal be church's last?

While playing nanny to the daughter of a suspected hitman, Chris is horrified by the child's revelation.

Leo finds himself in deep trouble with a group of armed robbers while Harris is having his own problems.

Harris is blackmailed by an adversary from his past who threatens to reveal his fire psychiatric disorder. Meanwhile, Angie receives a proposal of marriage.

Harris' blackmailer has more tricks up his sleeve which puts Angie's life on the line.

Bi-polar, confused, gun-toting, groom Luke is a bundle of nerves - but not over the big day.

The showdown between Harris and his blackmailer reaches a dramatic climax and Angie may pay the price.

Church unwillingly agrees to play Cupid for an informant and his estranged wife, until she is murdered.

Flynn finds himself in a treacherous love triangle when he is seduced by colleague.

A teenage love affair puts one of the team's children at risk on a major drug job.

Things quickly become more complicated in Angie and Luke's marriage.

Eight months have passed since Chris was shot by an unseen gunman, but the shooter's identity is still to be found.

Church goes undercover as a hitman in a desperate attempt to save a kidnapped girl.

Church's efforts to nail a high profile people smuggler are thrown into chaos by a rogue homicide detective.

Flynn wakes up in a hazy, drug-induced state next to the dead body of a prostitute.

A drug dealer offers to act as an informant in his father's drug organization. However, he has a condition: Chris must go on a date with him.

Despite agreeing to help her, Church is not convinced that he can trust the daughter of one of his informants.

Working undercover, a masked Leo is forced to steal the proceeds of an illegal poker game - and the main players happens to be none other than Peter Church and Brian Gray.

Flynn's old flame guides him deep into the world of body art, heroine and murder.

Chris suffers body blows when she is the forced to fight with her fists to nail a big time gangster.

Harris and Angie's son, Joshua, is abducted in a tragic case of mistaken identity.

Angie goes undercover to hunt down a serial killer who is praying on a popular tourist hotel.

Church risks radiation exposure in a desperate attempt to avert the detonation of a dirty bomb.

A stalled murder investigation forces Flynn to go undercover in a Middle Eastern consulate.

A domestic violence victim takes the law into her own hands.

A hitman target Chris when she investigates the sex murders of two teenage boys.

Luke Harris uses his bi-polar disorder as a cover to try and find a killer in a psychiatric clinic.

Apparently addicted to opium, Harris strikes a deal with a major drug dealer.

A revelation in a murder investigation suggests that the homeless are being exploited for snuff movies.

Harris goes undercover as a translator for a Malaysian drug cartel.

Church and Gray attempt to sting an allusive crook but they might have targeted the wrong man.

Betrayed by an old love, Church faces execution at the hand of a major drug dealer.

Angie Piper pursues a personal journey of revenge for the shocking death of her sister.

When a gay friend of Chris' commits suicide, Chris suspects he was murdered as part of a paedophile cover up.

Harris' complex relationship with his daughter threatens to implode.

Church hunts down a politically connected businessman importing cocaine.

Harris' opium addiction nearly costs him his life when he is exposed during an investigation.

Angie and Harris discover the shocking truth about their colleague, Megan Walsh.

Undercover as a hitman, Church is injured and suffers amnesia.

Accused of corruption and under investigation by IA, has Church reached his use-by date?

Flynn and Church are undercover in rival gangs when the city erupts into violence.

Angie goes undercover to bust a contract killer by posing as his long lost daughter.

The murder of an illegal immigrant leads undercover to a brothel trading in sex slaves.

Chris is involved in a car smash which leaves a young boys permanently disabled.

Harris' obsession with Angie's new partner spirals out of control when one of the Undercover unit falls victim to a serial killer.

Angie frantically tries to clear her lover's name while Harris works equally hard to convict him as the serial killer.