America's favourite baby-sitters are detectives, too!
When a big baking contest comes to Stoneybrook, Claudia can't wait to enter. Her excitement is catching, and soon the whole BSC is involved.
But Claud's very first cake falls, even though she was really careful. Her ingredients must have been tampered with. And Claudia's not the only baking victim. It looks as if someone is stirring up major mischief - by sabotaging other people's entries!
Claudia is determined to find out who's to blame. But she'll have to hurry . . . the competition is getting more dangerous every day!