Jack is dating Tania, whose mother, the communist Lady Leamington, gives a party to raise funds for the victims of Franco in the Spanish civil war. At his London practice Billy treats Bob Randall, son of Jack's old army sergeant Fred, wounded fighting for the Spanish Republicans. Aware that Jack considers himself in debt to Fred, who once saved his life, Jessie and Billy get Fred to act as go-between in persuading Jack to smuggle guns past Franco's blockade to help the Republicans. With Tania, Jessie - who has left Arthur - Billy and Left Wing journalist Nigel Scott-Palliser, Jack sets sail under the guise of a pleasure cruise.