The HMAS Hammersley confronts a series of new menaces in the northern waters from pirates to toxic crabs, not to mention a gorgeous solo yachtswomen with a rescue fetish.

The video of Chefo's bucks night finds its way into Kate's hands and she is humiliated by what she finds on it. The HMAS Hammersley comes across an unexploded sea mine and Spider manages to save the life of a boy who was near the mine, but have Spider's days in the navy come to an end?

Disaster looms for the Hammersley crew when a fire erupts in the engine room, after the mascot is stolen by a rival Patrol Boat crew. Meanwhile, an eye injury threatens to destroy Charge's career, and ET takes a vow of chastity in a desperate attempt to prove himself to Nikki.

The crew pursues a distraught father who has kidnapped his own children. Then, while searching a crocodile-infested swamp for the missing family, the crew discovers a badly mauled fisherman.

The Hammersley saves sailors from a sinking ship, only to learn they are diamond smugglers who will kill to save their cargo. Swain is kidnapped by smugglers and left trapped in their sinking ship. Will Buffer rescue him before the ship sinks? Mike is reprimanded by Navy brass over his obsession with the Bright Island mystery.

The Hammersley races to save a boatload of tourists from being murdered as part of a bizarre terrorist publicity stunt. Meanwhile, Swain and the crew help deliver the baby of a runaway teenager, found lost at sea with her criminal boyfriend. A series of emergencies at sea prevent Swain from attending the birth of his first baby.

After the Hammersley successfully pulls off the tricky evacuation of all the Australian citizens from an island in the Samaru Archipelago, it comes across an FFV which isn't what it pretends to be. Charge discovers first-hand exactly how dangerous his job can be. And Nikki and ET have to decide what to do now that they're working together.

An ugly hostage situation on board HMAS Hammersley sees two of the ship's female officers taken hostage below decks. It’s a day of high tension, which begins when a group of shipwrecked illegal immigrants is rescued from a sand bay. Along with Afghan refugees, and a chronically ill Asian girl, are three super-fit Eastern Europeans who waste no time once they are safe on board.

Robert fails a drug test but is determined to prove his innocence. Meanwhile, the Hammersley uncovers a smuggling operation by Samaruian rebels which is designed to destabilise the government.

The crew find a boy who has found a cache of guns. The boy is later kidnapped which ends up ruining a date for Kate and Jim. Meanwhile, one crew member faces losing the love of his life.

The Hammersley is once again in hot pursuit of the cabin cruiser responsible for trafficking weapons and ammunition to the Samaru Islands. Meanwhile Mike Flynn receives a tempting offer from Ray Walsman and Kate's life is placed in danger when she becomes isolated from the crew.

A change of command on HMAS Hammersley results in divided loyalties and the humiliation of the ship's most senior female officer. After a dangerous departure from Samaru, Commander Mike Flynn is recovering in hospital.

A new Commanding Officer and the discovery of a cruel and lucrative trade in crocodile skins results in some tense and disturbing moments for the crew of the HMAS Hammersley.

A kidnap drama on the ocean and relationship tremors below decks rock Hammersley as she sails the Coral Sea.

On patrol in the Arafura Sea, the Hammersley encounters an old adversary, an illegal foreign fishing vessel skippered by an infamous fisherman known as Hannibal. Robert is lost overboard in mysterious circumstances, sparking a major search and lives are at stake when Swain discovers rabies on board Hammersley.

The sinister business of organ harvesting sees two of the Hammersley's favourite sailors facing their own mortality.

Hammersley hunts down cattle rustlers behind the hijacking of live cattle shipments. Robert takes desperate measures to be seen as a team player by his crewmates, and Bird is terrorised by her ex-boyfriend.

Hammersley is caught in a war zone while delivering aid to a remote foreign island. Swain and Dutch risk their lives to rescue an aid worker and her sick patient from a deadly tribal feud. Mike faces a deadly dilemma when Bird is struck by a mystery illness and requires urgent evacuation.

Bomber faces disciplinary action after a violent confrontation with illegal fishermen. Kate is blinded by a deadly toxin, sparking a desperate race to find an antidote, and 2Dads' plan to help Bomber gain a promotion backfires when they are kidnapped.

Mike is tortured and faces death when he is captured by a ruthless gang of drug traffickers. Dutchy and the crew vow revenge when one of their mates is presumed murdered. After realising she has no romantic future with Mike, Kate makes a fateful decision about her career.

Kate is hunted down by an obsessed criminal after she kills his accomplice during a boarding. When Bird is kidnapped, the crew fears she will be murdered as payback.

Swain is obsessed with the mysterious sinking of a refugee boat. The crew uncovers a smuggling ring with a deadly method of sneaking goods into Australia, and Bird's romantic life is complicated when Mike's godson Ryan joins the crew of Hammersley.

As part of the boarding party checking a possible FFV, Dutchy doesn't hide his surprise at seeing one of the crew is SAS Captain Jim Roth. His flash of recognition is noticed by the ship's master, and the question now is, has Jim's cover been blown? ASIO "spook" Madelaine Cruise is furious. She confirms that Jim was on a mission and insists CO Mike Flynn shadow the vessel in case Jim needs assistance. And so he does, after Dutchy sees two men fighting on the deck, and the subsequent boarding party finds an area awash with blood and Jim under a tarpaulin with a serious head wound.

Robert becomes the lifeline when 2Dads is trapped alone in a sunken research submarine. Mike and the crew pursue a marine biologist suspected of sabotaging the submarine, and with 2Dad's air supply running out, Charge must use all his technical skills to help save his mate's life.

Dutchy and the crew are caught in a deadly fight for survival when a training exercise turns into a manhunt.

Bird is compromised when she discovers Ryan working for a private security firm while AWOL from the navy. Mike fears his son has been murdered by mercenaries and risks his career to get revenge on the killers. A pregnancy scare forces Kate to reconsider her future.