Will Ferrell

Sherlock Holmes

John C. Reilly

Dr. Watson

Rebecca Hall

Grace Hart

Rob Brydon

Inspector Lestrade

Kelly Macdonald

Martha Hudson

Lauren Lapkus

Millicent

Pam Ferris

Queen Victoria

Ralph Fiennes

James Moriarty

Adam Scherr

Brawn

Kieran O'Brien

Lestrade's PC Smalls

Noah Jupe

Doxy

Bella Ramsey

Flotsam

Colby Mulgrew

Hay Bag

Scarlet Grace

Pickle

Billy Jenkins

Mud Fog

Michael Culkin

Judge

Wolf Roth

Sigmund Freud

Jana Pérez

Lestrade's Wife

Nathan Osgood

Mark Twain

David Shackleton

Albert Einstein

Paul Cassidy

Charlie Chaplin

Bronson Webb

Jonathan Nightingale

Jamie-Rose Monk

Mrs. Nightingale

Jason Thorpe

Butler

Robert Cawsey

Waiter

Stanley Eldridge

Waiter

Oliver Maltman

Telegraph Operator

David Stoller

Hudson's Guard

Jack Riley

Newschild

Lilly Aspell

Newschild

Ethan Rouse

Newschild

Ellie Rose Eames

Newschild

Jamie Baughan

Titanic Ship Officer Liaison

Helen Duff

Titanic Guest

Jess Liaudin

Hangman

Wesley Kent-Hargreaves

Weird Child Companion

Daniel Fearn

Drooling Man Companion

Darren Lake

Disorientated Man Companion

Martin Bishop

Priest

Gerard Monaco

Titanic Ship Officer

Ben Lee

Houdini

Michael Buffer

Fight Fan #1

Bruce Buffer

Fight Fan #2

Russell Wilcox

Announcer

Billy Zane

Billy Zane

Hector Bateman-Harden

Young Sherlock Holmes (uncredited)

Codie-Lei Eastick

Young Watson (uncredited)

Laura Stevely

Sherlock's Mother (uncredited)

Layla Rose Boyce

Nicotine Stains / Nancy

Sadie Newman

Jane (uncredited)

Harry Baxendale

Seamus (uncredited)

Ella Bright

Bridgette (uncredited)

Kenneth Hadley

Headmaster (uncredited)

Paul Bigley

Teacher #1 (uncredited)

Sue Maund

Teacher #2 (uncredited)

Tommy Gene Surridge

Inky Hands (uncredited)

Paddy Holland

Tough Kid (uncredited)

Hugh Laurie

Mycroft Holmes (uncredited)

Steve Coogan

Gustav Klinger (uncredited)

Phil Hodges

Mr. Algernon Barkworth (uncredited)

Sara Beasley

Mrs. Frobisher (uncredited)

James Eeles

Mr. Petrucka (uncredited)

Paul T.T. Easter

John (uncredited)

Jordan Long

Herbert (uncredited)

Sonnyboy Skelton

Doxy's Dad (uncredited)

Willem Dalby

Newsie Man (uncredited)

Riley White

Jimmy (uncredited)

Lochlan White

Timmy (uncredited)

John Kinory

Instructing Solicitor (uncredited)

Benjamin Lok

Courtroom Person #3 (uncredited)

Joseph Macnab

Fitness Instructor (uncredited)

Martin Bassindale

One Man Band (uncredited)

Amelia O'Loughlin

White Star-Line Girl (uncredited)

Matthew Di Liello

Telly-Phone Assistant (uncredited)

Craig Thomas Lambert

Yeoman of the Guard (uncredited)

Jorge Leon

British Soldier (uncredited)

Martyn Mayger

Buckingham Palace Guest (uncredited)

Hugh O'Brien

Garden Party Guest (uncredited)

Deepak Anand

Nobleman (uncredited)

Shawn Dixon

Upper Class Gentleman #1 (uncredited)

Anthony Richard Rowe

Victorian Gentleman (uncredited)

Mick Slaney

Docker (uncredited)

Karl Farrer

Russian Merchant (uncredited)