The Red Herring (3rd book in the series Holmes and Holmes)

Mark (Doc) Watson tells Sherry and Holmes about a pawnbroker named Goodnight who gets paid $200 an hour to work crossword puzzles. They interview the man and learn he got the job at his assistant’s urging due to his having red hair. Then, because Holmes insists there must be a crime involved, Sherry and Watson follow his assistant to learn more. When the clues lead to an expensive jewelry store behind the pawnshop, both Tessa and Sherry’s actress mother, Fenella, get involved. Then Goodnight loses his cushy job, time is running out, and suddenly Labor Day is the missing link.