Before the days of Pop Idol, X Factor and then Britain’s Got Talent, there was another show that arguably became the template for TV talent shows that we've come to know so well.
One of the most successful talent-spotting shows of its time, Opportunity Knocks began life on BBC Radio in 1949 before coming to our TV screens in 1956. Hosted by Hughie Green, a second-run of the show came in 1964 until 1978 airing on ITV.
Rivalling BBC's New Faces, it was one of the most popular shows on British TV history, seeing thousands of hopefuls apply to perform on the show each week. Generations will remember tuning in to see singers, comedians, magicians and more compete, with the studio audience participating in a clap-o-meter for each act that wasn't included in the final result.