Mrs Murdock is in need of ‘a nice clean private detective,’ someone to investigate the theft of a rare gold coin, the Brasher Doubloon, the pride of her late husband’s private collection, normally kept under lock and key in a secure room in the house. As far as Mrs Murdock is concerned, the coin has been taken by her wayward daughter-in-law, the former nightclub singer, Linda Murdock, a woman she has never liked – both the coin and the girl disappeared at the same time, hence the suspicion surrounding her involvement in the case.