Kelly Clarkson may come across fellow celebrities nearly everyday, but that’s not to say she can’t be totally surprised by facts about them.

Earlier this week, the talk show host had NCIS: Los Angeles alum Chris O’Donnell on the show, who appeared on the beloved procedural for 14 years alongside LL Cool J.

And as the 9-1-1: Nashville star was sharing an old memory about his former co-star, the “Since U Been Gone” singer lost her focus as soon as she learned the “Going Back to Cali” rapper’s real name for the first time.

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While appearing on The Kelly Clarkson Show, after Chris was asked by Kelly if he’d ever worked out with LL, he told the story of how he pranked him with his cover of Men’s Health, about which he knew he “was gonna get a really hard time from him.”

His plan? Get the prop guy to create a fake advertisement inside the magazine featuring LL promoting some supplements. 

“The magazine comes out, we’re passing it around, and he’s just as I expected, making fun of me, and then someone’s page goes, ‘Oh Todd, you’re in here too,'” he shared, calling LL by his real name, and recalling how we was quick to pull out his Blackberry for a chat with his lawyers about someone using his likeness, before being told it was an April Fool’s joke.

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Kelly was certainly amused by the story, however she was more focused on the fact that she was learning the rapper’s real name for the first time. “Can we go back to where, I never thought — his name is Todd?!”

“Yeah, it’s James Todd Smith,” Chris said, reminding audiences of what LL Cool James stands for: “Ladies Love Cool James.”

“I’ve heard Cool James my whole life, but I almost didn’t hear the rest of the story, because I was like, ‘Who the hell is Todd?'” Kelly confessed, and, pointing to a photo of LL, joked: “That is not Todd, that does not look like a Todd.” 

“That’s amazing. That’s the best thing I’ve found out today,” she further quipped.

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LL is originally from Bay Shore, New York, and started rapping when he was ten years old. He initially went by J-Ski, but not wanting to associate himself with cocaine culture, later changed it to LL Cool J, a moniker coined by his friend and fellow rapper Mikey D.

He was signed by Def Jam Recordings in 1984, and the same year, he released the single “I Need a Beat,” followed by his debut studio album Radio the next year. He began acting around the same time, making his film debut by playing himself in the 1985 Krush Groove, loosely based on the early days of Def Jam.