Also wowing on the red carpet tonight are BAFTA nominated actresses Charlize Theron, Renée Zellweger, Margot Robbie and Scarlett Johansson.
The Duke and Duchess of Cambridge are also in attendance.
Graham Norton will host the British award ceremony which presents awards for Leading Actor and Actress, Original Screenplay and Best Film.
The BAFTAs 2020 have nominated 2019 film Joker for an impressive 11 awards.
The Irishman and Once Upon a Time… in Hollywood closely follow with ten nominations each.