Tim Pigott-Smith
— Charles
Charlotte Riley
— Kate Middleton
Oliver Chris
— William
Adam James
— Prime Minister Tristram Evans
Richard Goulding
— Harry
Max Bennett
— Coottsey
Tamara Lawrance
— Jess
Margot Leicester
— Camilla
Tim McMullan
— James Reiss
Priyanga Burford
— Mrs Stevens
Katie Brayben
— Diana
John Shrapnel
— Archbishop of Canterbury
Parth Thakerar
— Spencer
Grant Crookes
— Mourner
Philip Gascoyne
— Admiral (uncredited)