At 12 years old, O'Gorman was discovered by a casting agent during a school speech competition. After acting in a number of television roles and the Australian film The Rogue Stallion, he got a starring role in 1995 teen romance Bonjour Timothy, a performance which earned him a nomination for Best Actor at the Giffoni Film Festival in Italy.
He is known for The Hobbit trilogy, Young Hercules, and Trumbo.
