Alex Trebek Alex Trebek

Category: Cameos We Can't Wait to See. Jeopardy! host Alex Trebek will appear in the Christmas episode of How I Met Your Mother, show co-creator Carter Bays tells TV Guide Magazine exclusively.

"It's our twisted version of A Christmas Carol-type story," Bays says of the December 13 episode, titled "False Positive." "We see what it takes to get people back on track and start leading the life they're supposed to be leading."

Fun fact: Before finding his niche as the host of America's favorite quiz show, Trebek roomed in Los Angeles with recurring HIMYM guest and fellow Canadian Alan Thicke. "We were like the odd couple. He was the tidy one," says Thicke, who appears in the show's Robin Sparkles episodes. 

Subscribe to TV Guide Magazine now!