Some Women Won't Wait

An old and rheumatic man, (Bicknell) comes to the Cool & Lam agency seeking help for a young woman Mira Woolford) who is being blackmailed. Mira had married his partner and when the partner died, she inherited half of his substantial estate. His death was sudden, so there is some suspicion as to the cause. Mira is in Hawaii, so Bicknell hires Bertha and Donald to travel with him to the islands on a deluxe cruise ship.
Once they arrive in Hawaii, Donald manages to loosen Bertha up, getting her to wear Hawaiian dresses and even a bathing suit. Donald manages to befriend Mira and Norma, her friend with similar ambitions. There is more than one person attempting to blackmail Mira, and one of them gets a bullet between the eyes. Bertha and Bicknell discover the body in the victim's house and enter the crime scene and remove some evidence. This gets them in trouble and Donald manages to fix some of the damage. The suspicion falls on Mira, and Donald begins working to establish her innocence.
The murderer is exposed, largely due to police work. This book is different from most of the other Bertha Cool/Donald Lam books, in that the police are not nitwits. While it appears that Donald is a step ahead of the law, he is not. They are abreast of his every move and identify the killer before Donald does.