in English and was working towards a Ph.D. in medieval studies when he was spotted during a rehearsal of a university production by Clifford Williams of the Royal Shakespeare Company.
For his portrayal of Dr. Astrov in Toronto's Tarragon Theater production of Uncle Vanya, Hemblen received a Dora nomination for Best Leading Actor.
He voiced Magneto on the popular show X-Men: The Animated Series, the Night Master on Yin Yang Yo!, the Vaultkeeper in Tales from the Cryptkeeper, Lord Dread/Lyman Taggart on Captain Power and the Soldiers of the Future, and Asmodeus Poisonteeth in Redwall.
Hemblen played a ruthless henchman Jones in Short Circuit 2 (1988), Reverend Buckley in Where the Spirit Lives (1989), and appeared as Christopher Newport in Pocahontas: The Legend (1999).
He has also been featured in several Atom Egoyan films, such as Speaking Parts, The Sweet Hereafter (1997), Where the Truth Lies (2005), and Family Viewing (1987), for which he was nominated for a Genie Award.