From Wikipedia, the free encyclopedia. Michael Treanor (born April 17, 1979) is an actor and martial artist who starred in 3 Ninjas and 3 Ninjas Knuckle Up. He is the third son of Richard and Peggy Treanor. Treanor was discovered by casting agents for 3 Ninjas in his martial arts class. After encouragement from friends and family, he auditioned for and successfully landed the role of eldest brother Rocky. Treanor is a black belt and continues to practice as an adult. Description above from t...