Gary Lewis played Alator of the Catha as a guest star in the seventh episode of the fourth series of Merlin, called The Secret Sharer.
Lewis has appeared in the Scottish comedy Rab C Nesbitt and the criminal drama shows Taggart and Prime Suspect.
In 2010 Lewis appeared as Adam Ingram in the Channel 4 drama Mo a biopic of former Secretary of State for Northern Ireland Mo Mowlam, for this role he was nominated for a BAFTA Television Award in the category of Best Supporting Actor.
In 2011 Lewis appeared in episode five of new BBC drama Outcasts playing Patrick Baxter.