All Charlie Tickler wants is for his parents to listen. All Francine (a.k.a Frog) Castle wants is to be the world's greatest detective. So begins the friendship of Charlie and Frog, who soon become a crime-solving duo, restoring order to Castle-on-the-Hudson. Charlie, the new kid at the Castle School for the Deaf continues to find unexpected mysteries in the sleepy town of Castle-on-the-Hudson with Frog, his new friend and crime-solving partner. Just when Charlie thinks everything has settled down, a piece of the school's famous history goes missing, and it's up to the Charlie and Frog to solve the case, before it's too late.