Roy was born on April 21, 1963, in Quebec, Canada. He has one brother and one sister, Rodrick and Roxanne. His mother's name is Ryna. His family moved to a small town called Kapuskasing, which is located in Ontario, Canda. He is noted by his classmates as being a good athlete and also very shy. As a seventh grader he excelled in hockey, track and field, basketball and volleyball. That same year his family moved to Montreal, Quebec, Canada.

Roy did not start out wanting to be an actor. He was fascinated by science until he saw the movie Moliere. The next day, he dropped physics for theater and the rest is history. Roy's formal training came from the National Threatre School of Canada. He was one of two thousand people to be chosen for enrollment. The audition was not truly planned for by Roy. Instead of him auditioning for the School it was supposed to be one of his friends who in turn backed out and Roy took his place.

An accomplished Canadian actor on film and stage, Dupuis was first introduced to the American public as Oliva Dionne in Million Dollar Babies (1994), the story of the Dionne quintuplets. Followed by more screen appearances in American film like Bleeders(1995) or Screamers (1997), the handsome actor soon starred in La Femme Nikita.

Among his other film credits are Being at Home with Claude, Emily and the sequel Blanche and Les Filles de Calebs a very popular Quebec miniseries. Besides his work on TV and in Film, he has held the title roles for the theatrical productions of Romeo and Juliet and Harold and Maude.

He has been the recipient of various awards. Including, two consecutive Metrostars (Best Actor at the Gala Metrostar in 1991 and 1992, the Gemeau Award), Best Actor in a Drama Series for Les Filles de Caleb in 1992, and the Rose D'Or (a popular Canadian vote) for Actor of the Year in 1991.

This past year, Roy was named Most Desirable Man and Best Actor in the Best of Montreal vote from the Montreal Mirror.

Roy currently lives in Montreal, Quebec, Canada. He owns an 1840s farmhouse, which he enjoys working on in his free time. His other hobbies include, cross country skiing, skydiving and playing the Cello.