5 Crazy Things About the Crazy Ones Premiere

You might feel like you've just inhaled a 5-hour Energy shot after watching the pilot episode of The Crazy Ones (Thursday, 9/8c), CBS' new comedy that marks the return of Robin Williams and Sarah Michelle Gellar to network television. The two play father-daughter advertising team Simon and Sydney Roberts, and in the premiere they're trying to convince their firm's biggest client, McDonald's, not to drop them. Williams brings his typical frenetic energy to the role, tossing off one-liners and impersonations a mile a minute every time he's on the screen. Viewers, not to mention his co-stars, may get whiplash trying to keep up. But that's not the only nutty aspect of The Crazy Ones. Here are the five craziest things you'll see in the show's pilot episode:

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1. Kelly Clarkson: Yes, the original American Idol makes a hilarious guest appearance in the pilot episode as herself. Who knew she could act?! Her best scene: Recording a sultry McDonald's jingle with James Wolk that includes the line "It's not the meat, it's the motion." She totally owns it. Says Wolk of filming the scene: "It was so much fun, and she's wonderful."

2. James Wolk singing — twice! Wolk had a breakout role in this season of Mad Men as mysterious newbie Bob Benson, but here he'll explore the funnier side of the advertising world. In The Crazy Ones, Wolk plays Zach Cropper, the womanizing member of the team who helps Simon recruit Clarkson for the McDonald's campaign and then ends up performing a duet with her."He fancies himself a ladies man," Wolk tells TVGuide.com of his character. "But I think the interesting thing about Zack is that he's an amazing BS artist. ... I think we're going to see him kind of flying by the seat of his pants a lot, playing things off the cuff. But it will also be interesting to see a very human side to him."

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3. Robin Williams: Some of Williams' standout moments in the pilot include imitating a Native American shaman, fighting with a robot, and bantering with his control-freak daughter, Sydney. But the comedic legend promises that his role as Simon — who alludes to two past marriages and a stint in rehab in the pilot — won't just be a condensed stand-up routine week after week. "Riffing's one thing, but you have to have characters that make people want to come back," Williams tells TVGuide.com. "Occasionally there'll be the stuff that Mork & Mindy had. ... But the other idea is to keep dealing with complex things like fear, rejection. Things we deal with in the business. How do you overcome that?"

4. Outtakes: Be sure to stick around for the entire episode to catch some bloopers, including watching Clarkson try to keep a straight face as Williams and Wolk improvise a sexy jingle at their pitch meeting. "That scene was so much fun to shoot because we really were given the freedom to just go, and to just play," Wolk recalls. "We shot that over the course of a couple hours, and it seemed like we shot that over the course of about one minute because we were having so much fun. There was a lot of improv in that scene. ... It started to go off the rails in this great way, and we just went with it."

5. It's not all about comedy. Showrunners Tracy Poust and Jon Kinnally stress that The Crazy Ones is more than just a workplace comedy. There will be plenty of touching father/daughter moments throughout the course of the season. "He is afraid behind it all," Williams notes of Simon. "We have a moment where he's sitting in the office like, 'This didn't work.' There is that thing of, 'The net didn't appear. Uh oh. What do we do now, Coach?' And that's where I think [Sydney] steps up and keeps him going."

The Crazy Ones premieres Thursday at 9/8c on CBS. Will you watch?

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