World War II. Two British armoured cars suddenly come under heavy enemy fire, badly damaging one of them. The other continues its journey, arriving at a suspiciously undamaged bridge. Their orders were to stop before the bridge, but the tank commander decides that it's safe to cross. A newspaper announces that former playboy Vivian Kenway is missing in action.

Armistice Night, 1918. Young Vivian is carried through cheering crowds and fussed over by soldiers. He's going to Eton, and is acclaimed as a young man of a future bright and shiny with peace and plenty. But he is told never to forget the common fighting man.

Oxford, 1931. Vivian climbs a war memorial and hangs a chamber pot on it. He celebrates by going to the theatre with Jill, despite knowing that his best friend Sandy has designs on her. Sandy nonetheless waits up for him, concerned about Vivian's impending expulsion - but Vivian cheerfully predicts that it won't happen. He is wrong.

Vivian returns home on the day his father, Colonel Kenway MP, retains a safe Conservative seat. Vivian meets his new secretary, Jenny Calthrop, before having a heart-to-heart chat with his father, who is concerned about Vivian's prospects.

Sent to a South American coffee plantation to make something of himself, Vivian befriends Brumhead, a scientist who has devised a way of increasing output for no extra cost. But their boss isn't interested, as he keeps the price of coffee high by limiting output and indeed burning any excess. Brumhead is sacked, and Vivian leaves shortly afterwards, concluding that the coffee business is not for him.

He returns to London to discuss his future with his father, aunt and uncle. He admits that he doesn't know what he wants to do, but because of this he refuses to be pitchforked into a random job. His aunt threatens to cut off his allowance, but he can still borrow against his uncle George's legacy. As a result, he lives life to the full, the odd court fine for pinching policeman's helmets only enhancing his rakish reputation.

Sandy meets Vivian after a court appearance, and invites him to dinner. Vivian seduces his wife (his old flame Jill) after she admits she married Sandy for money. Sandy eventually discovers their affair, divorces her and starts a fight with Vivian when he bumps into him in a department store. Fleeing the shop's irate manager, they bury the hatchet in a nearby pub. Sandy says he'll probably take Jill back, and Vivian says he's going into motor racing.

His new career is initially promising, but the Austrian Grand Prix is cancelled due to the Hitler-Mussolini pact, and he runs out of money in Vienna. Suspecting his true financial position, his hotel manager prevents him from leaving until his cheque clears. Vivian meets a young woman, Rikki Krasner, who claims to be smitten with him - though subsequent interrogation reveals she's actually a Jewish heiress desperate to leave Nazi-occupied Austria. If Vivian marries her, her father will pay all his outstanding debts. After some hesitation, Vivian agrees.

The couple meet up in London, and decide to make a go of their marriage. But Rikki discovers that Vivian cheated her by claiming that his debts were three times bigger than they actually were - and the surplus money has been blown on a disastrous investment. Vivian is similarly shocked to hear that her father has no money left. She sells her wedding ring to pay the bill, and he apologises for his selfishness.

They visit Colonel Kenway in Cornwall, where Vivian starts an affair with Jenny. Finding out, Rikki tries to drown herself, but is rescued. Stricken with remorse, Vivian drinks heavily - and crashes his car, killing his father. Rikki divorces him, and Vivian sells his worldly goods, becoming a vacuum-cleaner salesman, with a job on the side as a dance-hall gigolo.

Jenny tracks him down and the two are reconciled. But when Vivian realises that he's part of a dying breed, he vows to do something with his life, and joins the Army. After a brilliant military career, he is killed in action - but in death achieves a reputation that dwarfs his past misdeeds.