Diamond and the Eye (A Detective Peter Diamond Mystery, Bk. 20)

If there's one thing detective Bath Peter Diamond has no patience for, it's a dumb git trying to get involved in one of his investigations—for example, a Philip Marlowe-wannabee private investigator like the self-styled Johnny Getz (his card claims he Getz results). But fate has saddled Diamond with this trial. A Bath antiques dealer, Septimus "Seppy" Hubbard, has disappeared without a trace, and his daughter, Ruby, has hired Johnny Getz to find him. When a dead body is discovered in Seppy's locked-up store, the missing persons case becomes a murder investigation, and now Diamond has to collaborate with the insufferable private eye.