Carolyn Keene 
Triple Hoax [EPUB ebook] 

When Nancys aunts friend is swindled out of a sizable sum of money, she invites Nancy, Bess, and George to New York to help figure out who is behind the theft. There, the girls see a performance of a magicians group who stun their audiences with clever sleight-of-hand tricks. Because the magicians temporarily remove peoples wallets and handbags, Nancy feels the actors arent above suspicion. But will her hunch lead them to solve the case?