For the first time in 11 years, host Ellen DeGeneres had to call in sick to her talk show, but as they say, the show must go on. And luckily, she found a very funny lady to fill in for the day — Ellie Kemper!

"The Office" and "Bridesmaids" star gamely took the reins for the Friday episode after DeGeneres came down with the flu.

This was a first. In 11 years, no one else has ever hosted my show. Thank you, Ellie! http://t.co/YHOu59jcyg — Ellen DeGeneres (@TheEllenShow) January 24, 2014

"I know what you're thinking: Ellen sure does look different in person," Kemper joked to the studio audience.

Kemper explained that DeGeneres had come down with "that terrible flu bug that's going around. It's bad. It's really sad. We've tented her and she'll be better soon."

At first, when Kemper got the call, she thought the host was pulling one of her famous pranks. "I actually thought it was Ellen's most elaborate scare ever," she said. "But it turns out it's working because I am scared right now!"

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She kept those fears at bay, though, and exuded her usual bubbly personality. It was a treat for the viewers, and more particularly the studio audience, since Kemper said they would all be brought back for one of DeGeneres's holiday giveaway tapings.

Though Kemper had a few kinks to iron out, like looking at the right camera, she quickly figured out what a good talk show host does. "Am I allowed to drink? Ellen would want that," Kemper said. "I'll do that backstage."

"Ellen" fans had no complaints about her performance!

Watching Ellie Kemper host @TheEllenShow show was the best thing to happen to today. Sooo funny. Happy Friday. — Shannon Thompson (@shannonthomps) January 24, 2014

Ellie Kemper hosting @TheEllenShow today was hysterical. Love her. I hope you get well soon Ellen! — Justine (@justinecashew) January 24, 2014