Lister signs himself up for the 'Canaries' mistakingly thinking that is it an a cappella singing troupe. Rimmer isn't too pleased when he finds out that Lister had signed him, Kryten, Kochanski, and Cat up too. The 'Canaries' are sent to an ocean planet to find out why the crew of a ship died. Onboard the ship they meet the onboard mainframe computer Cassandra. They find out that the computer has a special skill.