Katharine Hepburn plays Rose Sayer, the maiden-lady sister of a prim British missionary (Robert Morley). When invading Germans kill her brother and level the village, Charlie Allnut (Bogart in the role which won him his only Oscar), the slovenly, gin-swilling captain of a tramp steamer called the African Queen, offers to take Rose back to civilisation. She can’t tolerate his drinking or bad manners; he isn’t crazy about her imperious, judgmental attitude. However it does not take long before their passionate dislike turns to love. Together the disparate duo work to ensure their survival on the treacherous waters and devise an ingenious way to destroy a German gunboat.