The trio-Joe, James and Andy go to the circus to deliver two pails ordered by the circus lion trainer. Joe finds a toy crooked cat dropped by a snatch thief who stole it from the circus shooting gallery and returns it to Kent, the operator of the shooting gallery. Joe is attracted by the toy-crooked cat, and wins it at the  shooting gallery. Suddenly, a lion breaks loose from its cage and Joe has a narrow escape. The trio find that the lock of the lion cage had been tempered by someone. Andy does some investigation and finds out that the circus had been play plagued by a series of ‘accidents’ that appear to have a frequency and pattern that appear to be more than mere coincidences. Joe has ‘lost’ his crooked cat, and someone appears desperate to get hold of toy crooked cats with identical description as that which Joe lost. The trio get into tight spots in trying  to unravel the identity of the mystery crook in this gripping story that is full of suspense and drama.