This is a six-part documentary series which followed the crew of HMAS Rankin, a Collins-class submarine manufactured in Australia. The series was devised to give insight into life on board an Australian submarine and the series gives great insight into the cramped, noisy and claustrophobic conditions of submarine life. A typical day on a submarine is divided into four 6-hour slots, or watches, with most of the crew divided into two watches that each have 6 hours on and 6 hours off. The on-watch crew operate their equipment while the off-watch crew eat, sleep, read, study, watch television or use the limited fitness facilities. The crew, usually comprising about 45 people, are away from their families for lengthy periods, leading to strain on the families. The divorce rate among submariners is estimated to be as high as 80 per cent.