An Unforgettable Life

An Unforgettable Life is an upcoming episode from the twenty-third season.

Plot
One of Thomas's friends named Dory the Forgetful Blue Tang suffers from short-term memory loss. But, one day, she starts to remember a lot of things. Including the moment when Thomas and Ashima fell in love with each other.

Characters

 * Thomas
 * Edward
 * Henry
 * James
 * Percy
 * Toby
 * Emily
 * Duck
 * Donald and Douglas
 * Oliver
 * Toad
 * Trevor
 * Philip
 * Mavis
 * Ashima
 * Nia
 * Rebecca
 * Belle
 * Flynn
 * Annie and Clarabel
 * Dory
 * Marlin
 * Nemo
 * Hank
 * Lightning McQueen
 * Pingu
 * Tinky Winky
 * Dipsy
 * Laa-Laa
 * Po

UK, AUS and NZ

 * John Hasler as Thomas
 * Keith Wickham as Edward, Henry and Percy
 * Rob Rackstraw as James, Toby, Flynn and Donald
 * Nigel Pilkington as Trevor
 * Teresa Gallagher as Emily, Mavis, Belle, Annie and Clarabel
 * Steve Kynman as Duck
 * Joe Mills as Oliver, Toad and Douglas
 * Rasmus Hardiker as Philip
 * Tina Desai as Ashima
 * Yvonne Grundy as Nia
 * Rachel Miller as Rebecca
 * Ellen DeGeneres as Dory
 * Albert Brooks as Marlin
 * Hayden Rolance as Nemo
 * Ed O'Niel as Hank
 * Owen Wilson as Lightning McQueen
 * Simon Shelton as Tinky Winky (archive recordings)
 * John Simmit as Dipsy
 * Nikky Smedly as Laa-Laa
 * Pui Fan Lee as Po