Mila Kunis Ran Into Conan O'Brien While Lighting Fireworks — and He Reacted 'Like the Grinch'

Mila Kunis is reminiscing about last July 4 — when she had an unexpected run-in with a famous friend!

During an appearance on Conan Thursday, the actress, 37, recalled the last time she'd run into the show's host, Conan O'Brien. Their last interaction, Kunis explained, hadn't been so joyous an occasion.

She and husband Ashton Kutcher had decided to "legally" buy fireworks to put on a show for their kids over the holiday weekend in quarantine last year, she said, before making a joking shrug to indicate she wasn't exactly sure just how legal they were.

"And we're like, 'Listen, it's for the kids. No one's here. We'll just set them off on the beach. It's going to be safe.' He's from Iowa. He knows how to do this," she said.

As the fireworks were going off, O'Brien, who lives a few houses over, appeared — and he didn't seem thrilled about the disturbance, Kunis said.

"We are setting off said fireworks, and no one's on the beach—there's nobody there. And all of a sudden, fireworks like pew, pew, pew, pew. And then we see this, but with a hoodie," she said, impersonating O'Brien by crossing her arms and putting on a frown, as he apparently did when he walked toward them on the beach.

O'Brien protested the impersonation, telling Kunis: "I'm not Mr. Burns on The Simpsons!" However, Kunis doubled down on the impression saying: "You literally walked in like this."

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O'Brien quipped that he's "like the Grinch," before explaining that he had been concerned after hearing what he described as "major explosions" down on the beach.

"[Ashton] must know people in the military, because the reason I came over is I saw major explosions down the beach — and I'm on patrol, you know?" he joked. "These were the safest fireworks I've ever seen, that's for sure."

Kunis — who again assured O'Brien that the fireworks were legally purchased — explained that upon recognizing O'Brien, she ran toward him and went in for a hug before pulling back.

"All of a sudden, I was like, 'I don't know how to act,'" she said with a laugh.

Kunis has previously joked about life at home in quarantine with her two children, daughter Wyatt Isabelle, 6, and son Dimitri Portwood, 4, whom she shares with Kutcher. In February, she told Ellen DeGeneres that her kids had a way of seeking their parents out in lockdown no matter what.

"I love my kids very much, we both do, but they're like dogs: they can sniff you out!" she said. "They know your smell, they know what room you're hiding in — you can't get away from them. You just can't. They're just there."