Julian "Jules" Knight (n Kaye; born 22 September 1981) is an English actor and singer. He is best known for being a member of the British vocal group Blake and his portrayal of Harry Tressler in the medical drama Holby City. He left Blake in January 2013 and first appeared in Holby City as doctor Harry Tressler on 14 May 2013. Knight left Holby City on 14 April 2015.