A suicide bomb attack in a nightclub has a shocking impact on the crew of the HMAS Hammersley. Dutchy goes undercover with the SAS to catch a group of deadly extremists who are planning attacks on Australian targets.
Dutchy rescues a beautiful young woman, then finds that he is the prime suspect in a cold-blooded murder. The crew of the HMAS Hammersley rush to save a professional diver who is trapped in a shark cage. Mike puts his naval career on the line to help Kate to get her promotion. Kate has to make the most difficult decision of her life after she falls foul of Maxine.
Hammersley is in foreign waters assisting Madelaine Cruise on another clandestine ASIO mission. In a daring and dangerous evacuation on foreign soil, the RHIB party seek to rescue ASIO Agent Smith under gunfire.
Hammersley is deployed to intercept GD Security mercenary vessel, the MV Sassy and escort her back to port. Maxine asks for Mike's help in finding Ryan who went AWOL, having left before his discharge papers gone through.