Former CIA spy Bob Ho takes on his toughest assignment to date: looking after his girlfriend’s three kids, who haven’t exactly warmed to their mom’s beau. And when one of the youngsters accidentally downloads a top-secret formula, Bob’s longtime nemesis, a Russian terrorist, pays a visit to the family.

Ordered to teach a martial arts class of rambunctious bunny kittens, Po tells stories of each of the Furious Five’s pasts.