Irish actor Cillian Murphy won the Best Actor Oscar for his role in "Oppenheimer."

Cillian Murphy, the Irish actor best known for his roles in "Peaky Blinders" and "Inception," won the Best Actor Oscar for his role as physicist J. Robert Oppenheimer in Christopher Nolan's film "Oppenheimer." Murphy, who dedicated his win to "peacemakers," beat out strong competition including Bradley Cooper, Colman Domingo, Paul Giamatti, and Jeffrey Wright. This was Murphy's first Oscar nomination and win.