From Wikipedia:
Hollywood Screen Test was a talent show which aired on American Broadcasting Company from 1948 to 1953.
Debuting on 15 April 1948, and hosted first by Bert Lytell and then Neil Hamilton, Hollywood Screen Test sought to give exposure to many up-and-coming actors who were looking for their big break. The relatively unknown actors would be picked to guest star on the show, then they would have half-hour scenes of dialogue with established stage and screen actors.
Many stars were discovered on Hollywood Screen Test, including Grace Kelly, Jack Klugman, Pernell Roberts, and Jack Lemmon.
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