Suggestions by @desfitzgerald

Stephen Fry

as Flying Scotsman in Thomas & Friends

Score: +6

Stephen Mangan

as Neville in Thomas & Friends

Score: +4

Joe Mills

as Oliver in Thomas & Friends

Score: +8

Freddie Highmore

as Stepney in Thomas & Friends

Score: +2

Helena Bonham Carter

as Daisy in Thomas & Friends: Hero of the Rails

Score: +1

Richard Osman

as Harold in Thomas & Friends: Calling All Engines!

Score: +3

Kylie Minogue

as Caroline in Thomas and friends new year’s party

Score: +3

Joanna Lumley

as Elizabeth in Thomas and friends new year’s party

Score: +4

Brendan Gleeson

as Terence in Thomas and friends new year’s party

Score: +3

Helena Bonham Carter

as Daisy in Thomas and friends new year’s party

Score: +4

Emma Watson

as Mavis in Thomas and friends new year’s party

Score: +3

Mark Strong

as Boco in Thomas and friends new year’s party

Score: +4

Clancy Brown

as Salty in Thomas and friends new year’s party

Score: +2

Mel Gibson

as Trevor in Thomas and friends new year’s party

Score: +2

Richard Osman

as Harold in Thomas and friends new year’s party

Score: +3

Simon Pegg

as Bertie in Thomas and friends new year’s party

Score: +3

Lee Mack

as Rocky in Thomas and friends new year’s party

Score: +2

Julie Walters

as Old slow coach in Thomas and friends new year’s party

Score: +1

Eric Idle

as Toad in Thomas and friends new year’s party

Score: +1

Sally Hawkins

as Henrietta in Thomas and friends new year’s party

Score: 0