​From Wikipedia, the free encyclopedia Austin O'Brien (born May 11, 1981) is an American actor from Eugene, Oregon. He may be best known for playing the co-lead Danny Madigan in the Arnold Schwarzenegger-movie Last Action Hero, followed by his turn into romance as Nick Zsigmond in My Girl 2, and a part in both The Lawnmower Man and its sequel. O'Brien is the son of Valerian O'Brien and the older... see more