It features the ingenious valet, Jeeves, one of Wodehouse's best-loved characters, and has a minor role for his usual master, Bertie Wooster. The story was adapted from a play, for which Wodehouse required a romantic, happily-ever-after ending; reluctant to marry off the merry bachelor Wooster, he arranged for Jeeves to work for someone else for a change.
While Bertie is at a school for the idle rich, Jeeves takes work elsewhere, in the home of an impoverished Earl, Rowcester Abbey. While there, he helps unravel a complicated matter involving impersonated bookies, purloined gems, wealthy Americans and other Wodehousian tropes, all in the name of ensuring his employer William "Bill" Rowcester, the 9th Earl of Rowcester, can marry his girl Jill Wyvern.
Set in post-World War II Great Britain, where social changes have meant that the formerly idle rich have had to seek employment; Bertie Wooster, though himself not in poor fortune, is attending a school to educate the upper classes in how to fend for themselves, and in his absence, Jeeves has offered his services to William Belfry, the Earl of Rowcester, who is in poor fortune.
The story begins with a chance encounter in a pub between the wealthy widow Rosalinda Spottsworth and the white hunter Captain Biggar. The two had met previously on a hunting expedition when Mr Spottsworth was killed. Mrs Spottsworth is on her way to meet the Earl of Rowcester on the invitation of his sister Lady Monica, with the intention of buying Rowcester Abbey. Captain Biggar is in pursuit of a dishonest bookie - he had placed a £5 bet on two horses at high odds and won £3,000, only to discover that the bookie had absconded.
At Rowcester Abbey, Monica has arrived with her husband Sir Roderick to assist in the sale of the Abbey, and they are both surprised to find that the Earl is in better fortunes than they had last heard and now able even to afford servants. They are further surprised when they receive two phone calls; the first an anonymous inquiry regarding the Earl's car license plate number, and the second from the police.
When the Earl arrives (in his bookie disguise) he laments having ignored Jeeves' advice to lay off Captain Biggar's bet, and is shocked to find his sister and brother-in-law have come to visit. When told of the plan to sell, he is overjoyed, but thrown when it turns out that he had previously romanced Mrs Spottsworth (under her previous married name), and further thrown when Captain Biggar arrives and is invited to stay.
After initial threats from Captain Biggar, he, the Earl and Jeeves hatch a plan to steal a pendant belonging to Mrs Spottsworth, intending to pawn it, and to place the proceeds on an outsider bet at the Derby; Captain Biggar requires the money to feel worthy of proposing to Mrs Spottsworth, bound by a code which frowns on gold digging.
Though initial attempts to acquire the pendant serve only to alienate the Earl's fiancée, Jill Wyvern, and the sale of the house, which would have yielded deposit enough to recompense the Captain, are thwarted by the tactlessness of Sir Roderick; Jeeves comes up with a successful plan, which exploits Mrs Spottsworth's fascination in the supernatural.
On the day of the Derby the theft of the pendant is discovered and the police called. Jill's father, the Chief Constable, having heard of Jill's suspicions goes to the Abbey intending to horse whip the Earl. Although still angry, Jill warns Jeeves who in turn explains to her the goings-on she had misinterpreted as an affair. The Captain is suspected of the theft because of his absence, and hopes are dashed when the Captain's racing tip comes second in a photo finish. But everything turns out for the best after the Captain returns, having failed to pawn the pendant. He professes his love and explains his code, which Mrs Spottsworth laughs off with the news that one of his friends, to whom he felt bound under this code, had married a richer woman.
Jeeves steps in while announcing the engagement, with the suggestion that Mrs Spottsworth ship the house, brick by brick, to America and in doing so secures the sale. The tale ends with Jeeves handing in his notice, as Bertie Wooster has been expelled from the school for cheating.