Exclusive Sneak Peek: Josh Groban Woos Sarah Michelle Gellar on The Crazy Ones

Josh Groban is going Crazy.

The singer guest-stars on Thursday's episode of The Crazy Ones as a former co-worker of Sydney's (Sarah Michelle Gellar) who still carries quite a torch for her.

"He's a guy who has had kind of a defining moment in his life with Sydney, and he winds up kind of writing a song about her that she finds to be kind of creepy," Groban tells TVGuide.com of his character, Danny Chase. "She didn't really view it as, like, a deep friendship, but [Danny] always kind of thought she was [his] closest friend."

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Needless to say, Danny's attempt to woo uptight Sydney years later throws her for a loop. "She's taken aback by it for sure," Groban says. "She kind of doesn't know what to think. She's a little bit flattered, but then her co-workers are kind of like, 'Hey, this guy probably kills people.'"

Groban's role on The Crazy Ones isn't the first time he has displayed his comedic chops. He previously guest-starred on The Office and has made appearances in Jimmy Kimmel Live!sketches. But he says he was intrigued by the idea of having a new character to call his own. "I love taking these roles because it just gives me a chance to kind of spread out," he says. "I've done a few things where I've kind of played myself or like a bizarro version of myself, and I thought it would be fun to kind of go in there and not be, you know, the music guy."

So, did Groban channel any personal experiences for the role? "I'll write songs or sing songs about somebody that I'll be thinking about or something in my life that's happened," he admits. "But I kind of like to keep a little mystery to it personally with my songs. I would never put the name of somebody or the telephone number or something like that into one of my songs. But Danny's character is way less subtle than that."

Check out an exclusive clip of Groban's guest role below:

The Crazy Ones airs Thursdays at 9/8c on CBS.