It's 1955 and three people who were wartime friends are appalled to find they are fellow travellers on a small, old passenger liner on the round-Africa run on the ten-week. Elinor MacKenzie is in tourist class, in first class is Dr. Paddy Browm, who is convalescing from polio. George Ashden is still haunted by his unhappy marriage - and the memory of Elinor in 1945. When Paddy finally discovers the secret which Elinor has known since Genoa, his action forces the three old friends into inescapable proximity of passengers in the same class. As the ship ambles round Africa, the love story swings between vanished worlds.