Dr Sam Ryan investigates her first case as a police consultant - a tragic case involving the death of a child.

The murder investigation continues and someone breaks into Sam's house. Undeterred, she continues her search for the truth.

When Mark James's decomposing body is discovered, it bears all the signs of a ritualistic killing.

The police grow frustrated with the lack of a forensic link, but Sam finds more clues in an old case.

The death of a man in custody seems like a straightforward case, but DS Farmer has concerns about some of her officers.

Someone is harassing Sam as evidence of a cover-up mounts, and the bomb squad is called in to deal with a mysterious parcel.

Tragedy strikes after a student asks Sam for advice over her arranged marriage, and then sees her family torn apart.

Sam tries to persuade her student to reveal where her father is hiding. The tragedy spreads beyond the family, and even the team may be in danger.

A boxer dies from brain injuries mid-bout. A new DSI takes over the team's investigations. Sam and Wyn bury their mother.

Sam discovers why Kevin entered a bare knuckle fight, as well as uncovering evidence of more foul play in the boxing circuit.

Stuart Evans is in the advanced stages of Aids when he dies, and his body is donated to science. However a routine toxicology test reveals foul play was at work.

The police make an arrest, but do they have the right suspect? Sam pursues her own line of investigation.

The murder of a married woman who was having an affair seems straightforward. Friction develops between Dr Ryan and the police when the evidence complicates their case.

The murderer makes a direct threat against Sam's life after she uncovers the evidence needed to identify them.

The police suspect a violent alcoholic of the murder of an elderly woman. Sam clashes with the police when she refuses to support their case.

Sam's pursuit of her own theories leads her into dangerous places, both personally and professionally.

Sam must investigate a case with a painful personal connection when a close friend is murdered after the Cambridge May Ball.

The case becomes entangled in Annabelle's romantic relationships when Sam discovers her friend may have had an affair with a student.

A young woman is found dead in an empty house. Why was she there? Sam suspects another person was involved.

The hunt is on for Mr Harris, but the murderer may be closer to home. Meanwhile, Sam grows closer to surgeon James Reynolds.

A tragic scene is discovered when a young mother apparently dies of an overdose. When another addict dies in an explosion, Sam has a bigger case on her hands.

Are the deaths linked to a drug war or is this the work of vigilantes? Sam suspects a personal tragedy is at the heart of things.

The death of a farmer involving a combine harvester seems like an accident - until Sam receives an anonymous tip-off.

Sam looks for connections between Ian Neal and a killing in Northern Ireland in 1985. Meanwhile DI Connor's wife arrives in Cambridge.

Sam learns that the captain of the helicopter died of a heart attack, but she doesn't think it was the cause of the crash, and with 75 helicopters grounded, accident investigator Tony Newsome needs some answers.

Sam learns that the captain of the helicopter died of a heart attack, but she doesn't think it was the cause of the crash, and with 75 helicopters grounded, accident investigator Tony Newsome needs some answers.

A small-time criminal is the prime suspect in a gangland murder. Sam Ryan believes he may be innocent.

Sam challenges the police after an indepenedent postmortem into McNally's apparent suicide. Further deaths take place.

Sam searches for the identity of a victim of a cinema fire. A medical artist helps her reconstruct the face, but the result causes some embarassment for the police.

The identity of Body 10 reveals that a violent criminal may have been wrongly convicted of a murder. Sam and DCI Connor are eager to get the truth.

Two elderly brothers are found dead in their home, with no apparent injuries. A post mortem discovers suspicious puncture marks and a possible racist connection.

A third death helps Sam realise that the motive behind the murders of the Davies brothers was not racial - but revenge.

Sam is called in to identify the naked body of a woman uncovered on a ski slope in Norway.

DCI Norton dismisses Sam's idea that a serial killer is at work - until a third body is found at one of the victim's family homes.

A school director's wife commits suicide, but Sam suspects murder. During the investigation, she receives shocking news about her own health.

A second post-mortem is perfumed on Helen Dupen and, although Sam is obviously ill, she is determined to find more evidence.

Professor Leo Dalton and Dr Harry Cunningham join Sam Ryan in the investigation of a massive traffic accident in which not everything is as it seems.

Sam, Leo and Harry are at odds with the police investigators when a covert operation is exposed. But has Sam overstepped the mark this time?

The police bring in the team when a family is attacked in their own home, leaving the only survivors in critical condition.

A new murder turns DCI Ashton's suspicions toward the victim's family and friends, whilst Harry investigates a death that may be linked to the Irons family.

Murder is suspected when the body of a missing person is found hidden within a derelict factory, seven years since he was last seen alive.

As Sam searches for the killer of Marcus Saul, Harry finds himself involved in the tragic death of a student from the medical faculty.

The murder of a probation officer leads the team to the doorstep of a police cadet college, as they quickly establish a link to a similar murder just months before.

As the police investigate the possibility of a copycat killer among the students, a friend from the college pressures Sam to put loyalty above the truth as the case unfolds.

Sam is called after a suspected terrorist attack causes a fire at a hotel and a government minister is injured.

Sam delves deeper into the case but is undermined by the findings of an independent pathologist, brought in to conduct a second autopsy.

Sam comes under scrutiny at an official inquiry into two prison deaths and an old case Sam worked on 13 years resurfaces.

Sam uncovers a crippling truth about her involvement in a 13-year-old case -did she help convict an innocent man?

The body of a young pregnant sports agent is found in the grounds of her office building. Sam and her team uncover a tragic story of money and corruption.

Following her discovery of the second body and believing the cases to be linked, Sam is sidelined from the investigation as she attempts to get to the truth.

The Home Office ask Sam and her team to examine a number of times of death as given by a highly respected and internationally renowned independent pathologist, Peter Sachs.

Leo and Harry follow up their leads to discover an alarming truth. Are Sam and her team being used by the Home Office to drive out Peter Sachs in fear of a costly process?

The bodies of two young men are discovered, partially exposed, following a landslide on the coast of Northern Ireland.

The case takes an interesting turn when the bodies are identified as brothers who disappeared after a police questioning during the Troubles.

Suspicious symptoms afflicting a group of children on the coast may be linked to the death of a local man.

Leo hunts for the source of the children's symptoms before any more fatalities occur. Meanwhile Harry discovers the truth behind Nick Garner's death.

The death of a jockey during a race becomes more complicated when the horse's owners are killed in a helicopter crash.

Foul play is confirmed when it emerges that both the horse and the helicopter pilot were drugged. Could syndicate member Matt Gibb be responsible?

Leo and his team are approached by a support group to help discover the truth behind a train crash.

Leo, Harry and Nikki step up their efforts to discover the truth behind the train crash but there are still many unanswered questions.

Sam Ryan recruits the Lyell team to investigate the assassination of the health secretary, but Nikki is unsure whether Sam knows more than she's letting on.

DNA evidence linked to the health secretary’s assassination forces Nikki to face her past in the present. As her investigation progresses, Nikki realises that its consequences will affect her, and her profession, forever.

When a woman confesses to murdering her husband, the Lyell team must determine if all is as it seems. Meanwhile, Simone is shocked to be reunited with a detective from her childhood and struggles to untangle her past.

A secret from his father propels Jack to Belfast. Meanwhile, Simone and Nikki investigate the mystery of a burned body. As familial secrets come to the surface, Jack faces tragedy head on.

The death of an investigative journalist throws the spotlight on to Sam Ryan. Nikki begins to realise that the implications of her discoveries will challenge the principles of forensic science.

Events lead Nikki to conclude that getting the truth will put the Lyell team and everything they love in danger.