Suggestions by @jdfitzgerald

Sally Hawkins

as Henrietta in Fan Casting More Thomas Characters (Classic series only)

Timothy Dalton

as Skarloey in Fan Casting More Thomas Characters (Classic series only)

Alan Cumming

as Duncan The Grumpy Narrow-gauge Engine in Fan Casting More Thomas Characters (Classic series only)

David Tennant

as Donald The Scottish Twin Engine in Fan Casting More Thomas Characters (Classic series only)

Hayley Atwell

as Lady The Magical Engine in Fan Casting More Thomas Characters (Classic series only)

Daniel Radcliffe

as Bill And Ben The Tank Engine Twins in Fan Casting More Thomas Characters (Classic series only)

Clancy Brown

as Salty the dock yard diesel in Fan Casting More Thomas Characters (Classic series only)

Millie Bobby Brown

as Rosie the pink engine in Fan Casting More Thomas Characters (Classic series only)

Katie Leung

as Molly the yellow engine in Fan Casting More Thomas Characters (Classic series only)

Martin Freeman

as Iron Arry in Fan Casting More Thomas Characters (Classic series only)

Nick Frost

as Iron Bert in Fan Casting More Thomas Characters (Classic series only)

Simon Callow

as Mighty Mac in Fan Casting More Thomas Characters (Classic series only)

Anthony Hopkins

as Freddie in Fan Casting More Thomas Characters (Classic series only)

Colin McFarlane

as Murdoch the orange engine in Fan Casting More Thomas Characters (Classic series only)

Matt Lucas

as Fergus the railway traction engine in Fan Casting More Thomas Characters (Classic series only)

Eddie Izzard

as Arthur the large tank engine in Fan Casting More Thomas Characters (Classic series only)

Kelly Macdonald

as Emily the sterling engine in Fan Casting More Thomas Characters (Classic series only)

Freddie Highmore

as Ben in Fan Casting More Thomas Characters (Classic series only)

Daniel Radcliffe

as Bill in Fan Casting More Thomas Characters (Classic series only)

Steve Carell

as Sir Handel/Falcon in Fan Casting More Thomas Characters (Classic series only)