Simon Pegg as Dennis

Thandiwe Newton as Libby

Hank Azaria as Whit

Dylan Moran as Gordon

Harish Patel as Mr. Goshdashtidar

India de Beaufort as Maya Goshdashtidar

Matthew Fenton as Jake

Simon Day as Vincent

Ruth Sheen as Claudine

Nevan Finegan as Mickey

Tyrone Huggins as Grover

Iddo Goldberg as News Reporter

Ameet Chana as Taxi Driver

Chris Hollins as Himself

Denis Lewis as Herself

Sutara Gayle as Nurse

Gabriel Fleary as Drag Queen

Pandora Colin as Claire

Stephen Merchant as Man with Broken Leg

David Walliams as Man in Bakery

Hazel Douglas as Older Woman

Anna Tolputt as Receptionist

Simon Lenagan as Undercover Cop / Dad

David Cann as Marathon Official

T.R. Bowen as Doctor

Margaret John as Libby's Grandmother

Floella Benjamin as Libby's Mum

David Milner as Libby's Dad

Henrietta Clemett as Reception Nurse

Peter Serafinowicz as TV Commentator

Preston Nyman as Boating Boy (uncredited)

Rene Costa as Spectator (uncredited)