Ioan Gruffudd

Character: William Wilberforce

Romola Garai

Character: Barbara Spooner

Benedict Cumberbatch

Character: William Pitt

Albert Finney

Character: John Newton

Michael Gambon

Character: Lord Charles Fox

Rufus Sewell

Character: Thomas Clarkson

Youssou N'Dour

Character: Olaudah Equiano

Ciarán Hinds

Character: Lord Tarleton

Toby Jones

Character: Duke of Clarence

Nicholas Farrell

Character: Henry Thornton

Sylvestra Le Touzel

Character: Marianne Thornton

Jeremy Swift

Character: Richard the Butler

Stephen Campbell Moore

Character: James Stephen

Bill Paterson

Character: Lord Dundas

Nicholas Day

Character: Sir William Dolben

Georgie Glen

Character: Hannah More

Nicholas Woodeson

Character: Harrison

Tom Fisher

Character: John Ramsay

Richard Ridings

Character: Speaker of the House

David Hunt

Character: Lord Camden

David Toole

Character: Beggar

Alex Blake

Character: Heckler

Angie Wallis

Character: Marjorie

Harry Audley

Character: Edward Hope (Quaker)

Chris Barnes

Character: Michael Shaw (Quaker)

Tom Knight

Character: Physician

Andrew Whipp

Character: MP 1

Andrew Neil

Character: MP 2

Estelle Morgan

Character: Maid

Philip Dunbar

Character: Camber

Adam Woodroffe

Character: Parliamentary Clerk

Joseph Traynor

Character: Newton's Secretary

Simon Delaney

Character: Young Parliamentary Officer

Neville Phillips

Character: Old Parliamentary Official

Eki Maria

Character: Young African Woman

Daniel Naprous

Character: Delivery Coach Driver

Peter White

Character: Delivery Assistant