Opportunity Knocks is a British television and radio talent show presented by Hughie Green (1949-78), Bob Monkhouse (1987-9) & Les Dawson (1990). It was shown on ITV from 20 June 1956 to 29 August 1956. A second run commenced on 11 July 1964 and lasted until 20 March 1978. It was revived by the BBC from 21 March 1987 to 2 June 1990.