Longitude

Michael Gambon

John Harrison

Jeremy Irons

Rupert Gould

Gemma Jones

Elizabeth Harrison

Anna Chancellor

Muriel Gould

Emma Kay

Laura Gurney

Barbara Leigh-Hunt

Dodo Gould

Peter-Hugo Daly

John Jefferies

Alec McCowen

Sir Frank Dyson

Kevin Hudson

Lieutenant (uncredited)

T. P. McKenna

Edmund Burke

Peter Cartwright

Army Doctor

Alfred Burke

Rear Admiral

Jonathan Coy

Admiral Clowdisley

Christopher Hodsol

Captain Ainsley

Samuel West

Nevil Maskelyne

Clare Lawrence-Moody

Staff Nurse

Ian McNeice

Dr. Bliss

Clare McCarron

Nurse

Ian Hart

William Harrison

John Nettleton

Minister for the Navy

Bill Nighy

Lord Sandwich

Brian Cox

Lord Morton

Nigel Davenport

Sir Charles Pelham

Liam Jennings

Young William

John Leeson

BBC Producer

Joe Williams

Cecil Gould

Geoffrey Hutchings

Estate Manager

Nick Reding

Captain Campbell

John Wood

Edmund Halley

Peter Penry-Jones

Surgeon

Charles Edwards

Lt. Seward

David Wood

Ditton

Clive Francis

Captain Digges

Mark Tandy

Whiston

Stephen Fry

Sir Kenelm Digby

Steven Alvey

Learmouth

Tobias Menzies

Halley's Secretary

Ben Jones

Lt. Williams

Gary Waldhorn

Commodore Forrest

Robert Demeger

Observatory Porter