Before co-starring in the 2005 movie Syriana, he appeared in three British television shows: The Bill, Mile High, and Doctors.
Munir was born in London to British Pakistani parents, a carpenter and a seamstress.
He began his career by attending weekly drama workshops at the Theatre Royal Stratford East.
He was then contacted by Hampstead Theatre in London, who offered them a stage role in Local Boy.
Munir was well received in Syriana, where he played Wasim Khan, an unemployed Pakistani immigrant living in the Middle East; the New York Times praised his "delicate, watchful sensitivity".