Season 3

Pilot Alan Glenn in the new commander of Hero. His first trip is to check out an immobilized Soviet submarine, which as surfaced in the Arctic.

When the Hero is asked to intercept a vessel suspected of drug smuggling, Commander Glenn's loyalties are divided.

As Lt. Cmdr Beaumont considers taking unpaid leave for a yachting expedition, the HMS Hero encounters another lone yachtsman who's more experienced than he seems.

With the Hero in dock, about to take part in an important naval exercise, Commander Glenn is persuaded to spend the weekend with an old flame, and her husband. In his absence, Lieutenant Peek gets on the wrong side of the dockyard workers, and soon has the crew embroiled in a Union dispute.

Hero's continued lack of success in anti-submarine warfare exercises against HM Submarine Ovid rattle Captain Glenn's self-confidence and cause increasing tension between him and his officers.

A young nautical engineer has developed a new system of rudder stabilisation, and the Hero is chosen to test it.

Regulator Fuller is put in charge of 3D mess in a bid to curb the unruly behavior of AB Grogan and Smith who are picking on Seaman Dorrity.

An officer on board a neighbouring vessel dies in strange but unsuspicious circumstances. Unsuspicious, that is, until the body of an old girfriend of his, is washed up ashore on the same day.

With Commander Glenn now in charge of HMS Hero the ship prepares for a naval inspection. Assisting Rear Admiral Staunton in this task is Mark Nialls, formally much respected captain of HMS Hero.

Commander Glen's brother, Eddie, faces dismissal from the RAF after an unauthorised low flying stunt above a moving vehicle.

A Panamanian luxury yacht has gone missing, along with its millionaire owner and his family. After an RAF Nimrod on reconnaissance spots a similar yacht, several hundred miles from the missing yacht's last known position, the nearby HMS Hero is ordered to investigate.

When his wife arrives in port from Glasgow, Fuller doesn't get the nice surprise that the crew suppose. Meanwhile, the Chief Petty Officer, who has recent marital troubles of his own, faces possible disciplinary action for allowing his problems to affect his work.

Following a fire at a MoD scientific station, on an island called North Krona HMS Hero is ordered there. They are to deliver bulk feed items and offer any assistance with any rebuilding they may require.