Keeper of the Keys

In the 6th and final book in the mystery series featuring the Chinese-American detective Charlie Chan, we find our hero in Lake Tahoe, California. Chan has been invited as a house guest. He meets a glamorous Out of Printera singer, Ellen Landini, and she is murdered by a gunshot during a party. Her servants and four of her ex-husbands are suspects in the case, all with weak alibis. It is up to Chan to solve the murder. The clues are cryptic and misleading by nature: the singer's own revolver, two scarves, two cigarette boxes with mismatched lids, and the actions of a little dog named Trouble. Part of the solution to the mystery involves an elderly Chinese servant named Ah Sing--the keeper of the keys. Chan solves the case in his usual understated, spectacular fashion.