Grand Slam is an Americangame show based on the British series of the same name. Unlike the British series, which was played as a regular quiz show, the American version was conducted as a super-tournament featuring contestants who had appeared on other game shows.
The program featured 16 of the biggest winners in United States game show history in a single-elimination tournament. The contestants were seeded by the amount of money they won on their original show(s). The winner took home the $100,000 Grand Prize and a crystal trophy.
The contestants faced off against each other in a rapid-fire style series of questions. There were four rounds of questioning: General Knowledge, Numbers and Logic, Words and Letters, and "Mixed" (questions from all of the previous categories). Exclusively for the final match, a fifth "Contemporary Knowledge" round was added as round #3, between "Numbers and Logic" and "Words and Letters". In each round, the players were given one minute on their clocks, and the first contestant (determined by coin toss for the first round where the loser goes first; alternates for each subsequent round) was asked a question by the off-camera "Questioner", and his clock started counting down. The timing mechanics were similar to those of a chess clock; if a contestant answered correctly, his clock stopped, and his opponent's clock started running. If the active contestant answered incorrectly or passed, their clock continued to run and another question was asked.
When one contestant's clock expired, the round ended and whatever time the other player had remaining carried over. At the beginning of the final round, players' carried-over time was added to the one-minute base time. Once a player's clock ran out, the other player was declared the winner and moved on to the next round.
Each contestant was given three "switches" at the beginning of the game, and one more before the fourth round: by saying "switch", a player could stop their own clock and start their opponent's with the current question. Switches could be used consecutively (by saying "switch back") to switch the question back and forth between contestants.
Ken Jennings—Jeopardy! champion, winning more than $2.5 million over 75 games. In his initial run as champion Jennings set a new all-time winnings record. His 74-game winning streak remains a show record.
Kevin Olmstead—Contestant on Jeopardy! and on Who Wants to Be a Millionaire?. Olmstead is the biggest winner on Who Wants to Be a Millionaire, taking home a jackpot of $2.18 million; this broke a record set by David Legler and stood until Jennings topped it.
Ed Toutant—Winner of $1.86 million on Who Wants to Be a Millionaire? in 2001. At the time his win made him the second-biggest winner after Kevin Olmstead.
John Carpenter—First contestant to win $1 million on the American version of Who Wants to Be a Millionaire? in 1999. Carpenter later won $250,000 during Millionaire's Tournament of Champions. Carpenter was the first contestant to win $1 million in a single appearance on a game show.
Rahim Oberholtzer—Won $1.12 million on Twenty One in 2000. At the time of his win, Oberholtzer was the first contestant to win over $1 million on a game show.
Nancy Christy—First female winner of $1 million on Who Wants to Be a Millionaire?, accomplishing this feat in 2003. As of 2015, she is the last player to do so in a non-tournament setting.
Ogi Ogas—Won $500,000 on Who Wants to Be a Millionaire? in 2006.