Lady Gaga was not smitten with her fiance Taylor Kinney upon first laying eyes on him.

In fact, the handsome "Chicago P.D." star told "Watch What Happens" host Andy Cohen that Gaga slapped him during their initial meeting.

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Kinney was first introduced to Mother Monster on set of her music video "You and I" in 2011. "I show up and they're like, 'Oh this is the idea. This is the idea.' and I go, 'OK, just let me do my thing," he recalled. "And I remember I went up, and we're rolling, and I kissed her and she didn't expect it. They cut, and she slapped me."

While the first take was "awkward," Kinney and Gaga moved passed it. "The next take, I just did it again and then she didn't slap me. She didn't slap me then. We had a good time," he quipped. "I think there was chemistry. It was a late shoot. We were shooting until four or five in the morning. We exchanged information. A few weeks went by and we kept in touch and then that's that."

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Kinney and Gaga got engaged in February, the couple doesn't have too much planned as far as wedding arrangements are concerned. "We’re so busy," the 34-year-old actor told Cohen. "We’ve been engaged for less than a year. So, we’ve been talking about whether it’s New York, Los Angeles, destination place so we don't have an exact date yet."

ET spoke with Gaga not long after she got engaged, and she revealed Kinney's proposal prank. The 28-year-old pop star gushed, "It was actually funny, he first gave me a Ring Pop -- a candy Ring Pop -- and I was crying so hard, and I said yes right away, and then he pulled out the heart-shaped diamond and I said 'Oh, God!'"

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