What's My Line? Four panelists must determine guests' occupations - and, in the case of famous guests, while blindfolded, their identity - by asking only "yes" or "no" questions. Details Casts Galleries Posters Season Lists Title What's My Line? Genres Family Comedy First Air Date 1950-02-02 Last Air Date 1967-09-03 Episode Runtime 00 Hours 30 Minutes Total Season(s) 1 Total Episode(s) on All Seasons 876 Runtime 30 Production Companies Mark Goodson-Bill Todman Productions John Charles Daly... Self - Moderator... Original Size (1280x720) Original Size (2560x1440) Original Size (765x1147) Season 1 876 Episode(s) 1950-02-02