What's My Line?

What's My Line? is an American panel game show that premiered on CBS in 1950, in which a panel of four celebrity panelists questioned a guest with an unusual or noteworthy occupation, trying to determine what that occupation was through a series of yes or no questions, with a recurring segment in which a well known mystery guest appeared and the blindfolded panel tried to guess their identity. Broadcast live for most of its long run and noted for its urbane, ad libbed panelist banter, it became one of the longest running and most popular game shows of American television's first decades and a model for the celebrity panel game show format that followed it.