Alvin thinks of himself as an expert on spooky stuff such as vampires and werewolfs, so when a mysterous stranger moves in next door, Alvin's convinced he's a werewolf. Then, when Theodore gets bit by a "dog", he starts chewing socks, eating meaty stuff, and is a lot faster. Even Simon things something's not right. But at the moment, he's more like a warepuppy. They now have to find a way to cure him before the next full moon--durring the school play, "Dr. Jekyll and Mr. Hyde"--, or else Theodore will become a full werewolf--forever!moreless