Jemima Khan poses for photographers on arrival for the Unicef Halloween Ball in Mayfair, central London. (AP)
Hugh Grant dressed as a wild animal in a tan onesie and furry headdress. (AP)
Poppy Delevingne (AP)
Rita Ora made a late arrival wearing a Balmain jacket and thigh-high boots. (AP)
Greg Williams and Alice Temperley (AP)
Steve Coogan and Daisy Lewis (AP)
Arizona Muse (AP)
Jessie Ware (AP)