At 132 centimetres (4 ft 4 in) tall,[1] he has often been cast as diminutive characters, such as Teeny Weeny in The NeverEnding Story, all the Oompa-Loompas in Charlie and the Chocolate Factory, Keenser in Star Trek and its sequels, and in television series such as The X-Files, Doctor Who, and Eastbound & Down.

He later enrolled in The Slim Wood School of Comedy and got his start in the entertainment arena in England in 1970 as a stand-up comic in local cabaret clubs.

He has worked for Burton in three other films, Big Fish (2003), Corpse Bride (2005), where he supplied General Bonesapart's voice, and Charlie and the Chocolate Factory (also 2005).

He has performed many other roles in films and on television, including The X-Files, Flash Gordon, Return to Oz (as the Tin Woodman), Jim Henson's The Dark Crystal as a puppeteer extra, The NeverEnding Story as Teeny Weeny, the rider of the "racing snail", Alien from L.A., Howling VI: The Freaks as Mr Toones and Return of the Jedi as Droopy McCool.

In one of his more prominent speaking roles, Roy played Aaron, a violent Mumbai-born Mexican criminal in the second season of the HBO comedy Eastbound & Down.