Olivia Colman Queen Elizabeth II Actor Tobias Menzies Prince Phillip Actor Gillian Anderson Prime Minister Margaret Thatcher Actor Emma Corrin Young Lady Diana Spencer Actor Josh O'Connor Prince Charles Actor Helena Bonham Carter Princess Margaret Actor Erin Doherty Princess Anne Actor Peter Morgan Writer, Executive Producer Stephen Daldry Executive Producer Philip Martin Executive Producer Andy Harries Executive Producer Suzanne Mackie Executive Producer Tanya Seghatchian Executive Producer Robert Fox Executive Producer Matthew Byam-Shaw Executive Producer