Jessi recently moved to Stoneybrook and is one of the newest members of The Baby-sitters Club. She`s getting ready to start regularly sitting for the BSC`s newest charge, Matt Braddock. Matt has been Deaf since birth and uses sign language to communicate, so Jessi has to use it, too. It`s a secret language! Soon all the neighborhood kids want to learn how to sign, which keeps the BSC busy. Jessi`s the busiest of all -- she`s preparing for her dance school`s big show, plus working on another secret, just for Matt. Will Jessi be able to keep the secret and pull off her performance?