Robert Downey Jr. Dr. John Dolittle
Emma Thompson Poly (voice)
Rami Malek Chee-Chee (voice)
Tom Holland Jip (voice)
John Cena Yoshi (voice)
Antonio Banderas King Rassouli
Ralph Fiennes Barry (voice)
Marion Cotillard Tutu (voice)
Will Arnett Rabbit (voice) (uncredited)
Ralph Ineson Arnall Stubbins
Jessie Buckley Queen Victoria
Jim Broadbent Lord Thomas Badgley
Michael Sheen Dr. Blair Müdfly
Jason Mantzoukas James the Dragonfly (voice)
Frances de la Tour Dragon (voice)
Clive Francis Archbishop
Selena Gomez Betsy (voice)
Kasia Smutniak Lily Dolittle
Octavia Spencer Dab-Dab (voice)
Craig Robinson Kevin (voice)
Harley Durst Stunts
Joanna Page Bethan Stubbins
Harry Collett Tommy Stubbins
Gary Arthurs Stunts
Benjamin Ashley Stunts
Stewart Scudamore Pirate
Edgardo Simone Orchestrator
Kumail Nanjiani Plimpton (voice)
Paul Ginns Stunts
Samson Kayo Pirate
Lloyd Bass Stunts
Scott Menville Army Ant (voice)
Joey Coughlin Second Assistant Director
Kelly Stables Mouse (voice)
Matt King Clyde
Dave Hamilton-Green "B" Camera Operator
Marco Scotti Costume Supervisor
Danny Elfman Original Music Composer
Oleg Podobin Stunts
Nick Moore Additional Editing
Tim Treloar Humphrey the Whale (voice)
Alexander Bracq Stunts
Sid Sagar Jeff the Prisoner
Malcolm McLean "C" Camera Operator
Douglas Robson Stunts
Sonny Ashbourne Serkis Arnall Stubbins Jr.
Ranjani Brow Mouse (voice)
Frank Cuomo Production Manager
Emily Brockmann Casting Associate
Susan Downey Producer
Matthew Stirling Stunts
Frank A. Montaño Sound Re-Recording Mixer
Jon Mone Executive Producer
Shaun McKee On Set Yoshi / Animal Performer
Joseph Balderrama Prisoner
Sebastian Lochmann Concept Artist
Joe Kennard Stunts
Dan Gregor Screenplay
Rachelle Beinart Stunt Double
Tilly Powell Stunts
Stephen Gaghan Director, Screenplay
Stephen W. Schriver Stunt Double
Fraser Taggart Second Unit Director of Photography
Chris Pollard Stunts
Paula Price Makeup Artist
Doug Mand Screenplay
Oliver Chris Sir Gareth
Gary Tomkins Art Direction
Simon Crane Second Unit Director, Stunt Coordinator
Adam Collins Stunts
Lucy Bevan Casting
Chris Lebenzon Editor