Mr. Young (2011)

Season 3: Episode 27

Dang is called back to Vietnam to take over for Master Ki as guardian of his village. The gang heads to Vietnam to try and convince Dang to come back to Finnegan for graduation. While there, Adam discovers an ancient scroll that points to the mythical fountain of youth, which if found, could make Master Ki young again, releasing Dang from his duties. But to find the fountain, Adam must go up against Echo who is trying to preserve the leaf monkey habitat.