The comicbook store owner Stuart has been promoted to a show regular on The Big Bang Theory for the sixth season of the comedy.

Stuart, who is played by Kevin Sussman, will appear in up to thirteen episodes of the coming season which hints he may become better friends with the core characters.

His promotion from recurring character to series regular follows those of Melissa Rauch (Bernadette) and Mayim Bialik (Amy) who became regulars last season.

The Big Bang Theory returns in the US on September 27.