October, 1962. If the Cuban gamble goes wrong and war breaks out, Britain will no longer exist. London dispatches a secret envoy to defuse the confrontation. Catesby is sent to Havana and Washington to make clandestine contacts. London has authorised Catesby to offer Moscow a secret deal to break the deadlock. But before that can happen, Catesby meets the Midnight Swimmer, who has a chilling message for Washington.