The Alden children are off on another adventure---this time to New York City! The kids are so excited to finally see all of the exciting sites in the city, but discover a mystery on their hands at the hotel. When someone dyes the water in the pool purple, messes up guests' rooms, and ruins the guests' meals, the Boxcar Children are sure that there is someone behind it all. Can they figure out whodunit and solve the mystery before it's too late? #38 in the series.