Born and raised in Montreal, Ramsay's screen debut was opposite fellow Montrealer Elias Koteas in the film Malarek (1988). Ramsay and Koteas went on to appear in two other films together, Hit Me (1996), and Dommage collatéral (2002).
Ramsay's first lead in a major motion picture came when he was cast as Carlitos Paez in director Frank Marshall's film Les survivants (1993), the biographical survival drama based upon Piers Paul Read's 1974 book Alive: The Story of the Andes Survivors, which detailed the story of the Uruguayan rugby team that crashed into the Andes mountains.
In 2011 Ramsay made his directorial debut with Hamlet (2011). Ramsay also produced, wrote the adaptation, and starred as Hamlet. Hamlet (2011) premiered in competition at the Vancouver Film Festival in 2012.
More recently, Ramsay appeared as the jaded house boy Carlucci opposite Michael Douglas and Matt Damon in Ma vie avec Liberace (2013), directed by Steven Soderbergh about the last ten years in the life of pianist Liberace. Behind the Candelabra marked the second time that Ramsay had worked with Soderbergh. In 1995 Ramsay appeared in The Professional Man, part of The Showtime film noir series, Fallen Angels, starring opposite Peter Coyote, and Brendan Fraser.
