Orser was born in San Francisco, California. He married Irish Actress Roma Downey in 1987; they divorced in 1989. In 2000, he married Jeanne Tripplehorn; they have one son.
Orser made his television debut in 1991 on the series Gabriel's Fire. His next roles were small roles on The Golden Girls, Cheers, L.A. Law, The X-Files, NYPD Blue, Law & Order: Special Victims Unit and CSI: Crime Scene Investigation.
He played the antagonist Richard Thompson in the Denzel Washington thriller The Bone Collector (1999). In 2001, he had a small role in Pearl Harbor as an injured man saved by Kate Beckinsale's character. In 2003, he appeared as Wesley in the comic-turned-film Daredevil. He appeared in Saving Private Ryan as the traumatized pilot of a crashed glider.
He played Ansel in the drama thriller film Faults. From 2004-09, he played Chief of Surgery Dr. Lucien Dubenko, a recurring character, on ER. Most recently he has appeared in all three of the Taken film series as "Sam".
