Jack really wants to impress his diving coach dad ... there's just one problem. Jack is the worst diver in the worst diving team in Damp Bottom, England. But when a new kid starts at school with magic swimming skills and an eagerness to share tips, Jack's luck might be about to change.

But when Jack's new friend gets into trouble - and the fate of a secret world hangs in the balance - it's up to Jack and the rest of his diving crew to save the day. Sometimes it's not about winning, it's about helping your friends when they need it the most, it's about team work...