Photographer Jeff Troy and his wife Haila are visiting Central Park and run into a group of adult enthusiasts for model boats, which they sail in the lake. When one of them is found impossibly murdered (he's sitting on a rocky knoll and no-one approaches him before he's stabbed), the wife of one of the suspects hires Jeff for the princely sum of $1000--well, it's 1944 and that's a lot of money. Jeff doesn't want to investigate, but Haila insists, and they find themselves questioning a lot of different suspects and getting in a lot of trouble. Humorous, light-hearted, sometimes spooky--the Troys cover a lot of ground until they identify the not-at-all lighthearted motive for murder.