Pat Sajak switched places with Alex Trebek on April Fools’ Day in 1997.
The stunt involved the two best-known American game-show hosts of the era. Sajak, the longtime host of Wheel of Fortune, temporarily hosted Jeopardy!, while Trebek took over Wheel of Fortune. The unusual swap was presented as an April Fools’ joke and gave viewers a chance to see each host handle the other show’s format.
Trebek did not host Wheel of Fortune entirely alone: Sajak’s wife, Lesly, appeared as his co-host. Sajak and Wheel of Fortune announcer and co-host Vanna White participated as contestants on Jeopardy!, with the winnings directed to charity. The event therefore changed both the hosts and some of the on-screen roles.
A common mix-up is to identify the answer as Vanna White because she was closely associated with Wheel of Fortune, or to name Trebek himself because the question mentions him. The host who traded places with Trebek was specifically Pat Sajak, and the swap took place on April 1, 1997.