'The biggest audience laughs we got from any show. Why didn't we use laughing gas more often?' - Doug Naylor on Cassandra. On Holly's advice, Lister joins the 'Canaries'. He thinks it's the prison choir, actually it's a battle-hardened convict army, trained to go on suicide missions. And he's also enrolled Rimmer, probably the yellowest of yellowbellies in the whole universe. On their first mission, Rimmer meets Cassandra, a computer with the ability to predict the future with 100 percent accuracy, which prophesies his imminent death.