Gary Oldman was named Best Actor in a Leading Role for 'Darkest Hour' while Frances McDormand won Best Actress Oscar for 'Three Billboards Outside Ebbing, Missouri' at the 90th Academy Awards. Meanwhile, Sam Rockwell won Best Actor in a Supporting Role for 'Three Billboards Outside Ebbing, Missouri' while Allison Janney won best supporting actress for 'I, Tonya'.