Bill Todman

Contestants with unusual occupations were interviewed by the panelists. Only questions that could be answered with a "yes" or "no" were allowed. At the conclusion of the questioning, the panelists attempted to guess the contestants occupation. There was also a "mystery guest", usually a famous person; the panelists had to wear masks when questioning this person and the guest usually disguised his/her voice.

What's My Line' was a panel show in which 4 celebrities had to work out the occupations of a series of invited guests. An amazing variety of occupations turned up, many of them of an obscure working-class nature with which the panelists would be completely unfamiliar. They also had a celebrity guest on each week for whom the panelists had to cover their eyes.