Hayden-Smith appeared in the episodes "Rise of the Cybermen", "The Age of Steel" and "Doomsday" as Jake Simmonds in the 2006 series of Doctor Who. He returned to CBBC having completed the filming, but decided that he wished to concentrate on acting. His final day of presenting was on 7 July 2006, the day before his third and final Doctor Who appearance. On leaving CBBC and after his final Doctor Who appearance, Hayden-Smith played Romeo in Shakespeare's Romeo and Juliet at the Jermyn Street Theatre, London, 21 April – 17 May 2008. His position as Jake Simmonds on Doctor Who earned him a spot on The Weakest Link. In the first round, he banked the £5,000 target. Eventually, he placed fifth.