Marsden and Mirren sittin' in a tree, k-i-s-s-i-n-g! James Marsden got quite the shock recently when his celebrity crush Helen Mirren surprised him during The Ellen DeGeneres Show.

Marsden, 43, and Mirren, 71, were both guests on the daytime talk show on Monday, November 28. "I just love her. I do. I've had a massive crush on her for years," he said, blushing. "[I] didn't meet her backstage."

Marsden held back from introducing himself because of an embarrassing story, which he decided to share with the viewers.

"I'm glad I'm waiting to be on national television to admit this. But I was on a flight with her once to Rome. And when I got off the flight, I followed her to baggage claim and in a very voyeuristic, creepy way I took a photo of her while she was walking," Marsden told Ellen DeGeneres, laughing. "Very creepy! I was avoiding seeing her backstage because I didn't want her to know I was stalking her in Rome in an international airport."

Too late! DeGeneres, 58, then invited the Oscar winner out on stage to meet Marsden. Mirren pretended to snap photos of the Westworld actor and revealed that her husband, Taylor Hackford, was also in the pic that Marsden sneakily took at the airport. The two kissed on the lips and posed for a photo together.

"You're so handsome, oh my God," Mirren said.

Marsden fell to his knees (and turned beet red!) and escorted the Queen actress off camera shortly after. "I just had to give her my digits right now," he joked.

"Wow, you're trying to break up her marriage," DeGeneres said.

The 27 Dresses star replied: "I know. You get one shot in life! That was my one shot. Thank you, what a nice Christmas gift that was."

Watch Marsden and Mirren smooch in the video above!

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