Voice Cast-in Order of Appearance:
Richard E. Grant-Lord Haven
Jodie Whittaker-Alexandra
Jeremy Clarkson-Captain Charles
Richard Hammond-Porter
Keith Whickam-Salty, Assorted Voices
Kimiko Glenn-Izzy Moonbow, Sugar Moonlight
James Marsden-Hitch Trailblazer, Angus
Liza Koshy-Zipp Storm
Vanessa Hudgens-Sunny Starscout
Bahia Watson-Misty, Rosedust, Assorted Voices
Athena Kakarnis-Opaline
Sofia Carson-Pipp Petals
Rob Cullen-Rob
Bob Golding-Baz
Robert Rackstraw-Bernie
James May-Ray
Joseph Swash-Bellerophon
Geoffrey Rush-P.T.Boomer
Sam Heughan-Fraser
Michael McKean-Argyle Starshine
Jeremy Irons-The Reverend Wilbert Awdry, Thornaby
Tara Strong-Goldie
Gwion Rhys Davies-Rhys
A. J. Bridel-Tinsley, Pony Pipp Petals, Onyx
Anna May-Truong-Posey Bloom
Samantha Bielanski-Jazz Hooves
Jane Krakowski-Lady Haven
Nathan Evans-Harvey
MacKenzie Crook-Brookes
Aaron Barashi-AEG Thomas
Neil Crone-AEG Gordon
Adam Driver-Emperor Hatt
J. J. Gerber-Pony Hitch Trailblazer
Jenna Warren-Pony Sunny Starscout, AEG Carly
Ana Sani-Pony Izzy Moonbow
Maitreyi Ramakrishnan-Pony Zipp Storm
Jai Armstrong-AEG Harold
Will Harrison-Wallace-AEG Cranky
Jeremy Brown-Himself
John 'Lefty' Lethbridge-Himself
The Fisherman's Friends-Themselves
Toby Jones-Nigel
Simon Farnaby-Hector
Steve Blum-Isaac Moonbow
Kerry Shale-Cyril
Sunny and her friends will return in Thomas and Friends: Race to the Edge!