During the 1950s Twenty One was one of the most popular quiz shows on TV. Its ratings soared when Charles Van Doren, son of Pulitzer Prize-winning poet Mark Van Doren, appeared as a contestant on the show in late 1956. Van Doren seemed unbeatable. For week after week he answered every question correctly, winning a total of $129,000. But in 1957 a previous contestant, Herbert Stempel, revealed that the entire show was rigged. Van Doren, it turned out, was being fed the correct answers. A congressional investigation followed, and NBC, the producer of the show, issued an embarrassed confession.