Before Midnight (Nero Wolfe #25)

Cheaters never prosper, but Nero Wolfe encounters one who kills trying. At the Pour Amour perfume riddle contest, a million dollars goes to the contestant who can answer five questions. Someone doesn't like the heat of competition, so he murders the contest founder and steals the answers to the riddles. Now Wolfe has to sniff down a trail of clues that leads disturbingly close to home.