"The $64,000 Question" was based on the old radio program, "Take it or Leave It," which had a $64 top prize. Contestants who appeared on the show answered questions in one single category (e.g., Shakespeare, the Bible, American History or boxing). The first question was worth $64, and doubled as the questions increased in difficulty, up to that breathtakingly difficult $64,000 question. If the contestant reached the $1,000 plateau, the contestant returned to the next show to answer one question each week (the questions brought out by a bank executive and two security guards), so long as he/she kept winning. At the $4,000 plateau, he/she was placed in an on-stage isolation chamber; at the $8,000 plateau, any incorrect answer guaranteed the contestant a Cadillac Series 62 sedan as a consolation prize. At the $64,000, the contestant was given some reference material to study and/or could enlist the aid of an expert to help him/her answer the $64,000 question.