James McAvoy
— Brian Jackson
Alice Eve
— Alice Harbinson
Rebecca Hall
— Rebecca Epstein
Catherine Tate
— Julie Jackson
Dominic Cooper
— Spencer
Benedict Cumberbatch
— Patrick Watts
James Corden
— Tone
Mark Gatiss
— Bamber Gascoigne
Guy Henry
— Dr. Morrison
John Henshaw
— Des
Elaine Tan
— Lucy Chang
Simon Woods
— Josh
Charles Dance
— Michael Harbinson
Lindsay Duncan
— Rose Harbison
Sule Rimi
— Marcus
Ian Bonar
— Colin
Nicholas Gleaves
— Speaker for Nuclear Disarmament
Joe Van Moyland
— Hippy at Party
James Gaddas
— Martin Jackson
Joseph Friend
— Young Brian
Rasmus Hardiker
— University Challenge Competitor
Robert Cawsey
— University Challenge Competitor
Ben Willbond
— University Challenge Coordinator
Su Elliot
— Cleaner
Reuben-Henry Biggs
— Anthony Salmon
Bethan Bevan
— Cordelia Sykes
Tom Allen
— Tristram Neville
Raj Ghatak
— Nigel De Havilland
Kenneth Hadley
— Television Director
Gerard Monaco
— Waiter