Kirsten Dunst has been into Garrett Hedlund for months, but it wasn't until the Sundance Film Festival that they finally took their romance public.

The 29-year-old Melancholia actress was spotted kissing the Country Strong star at Monday's Bachelorette after party in Park City, Utah, multiple eyewitnesses tell Us Weekly.

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"Before leaving the party at 1:30 a.m., Kirsten and Garrett stopped to make out in the middle of the bar," one onlooker says. "He put his arm around her and then she pulled back and then they kissed again."

A second eyewitness adds that "they were dancing to Sam Ronson's set and stayed on the dance floor most of the time."

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When they weren't packing on the PDA, Dunst and Hedlund, 27, were chatting up fellow A-listers like Rashida Jones and James Marsden.

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Despite their affectionate outing, don't expect the couple to make any red carpet appearances in the near future. "They have hung out and they hook up, but it's nothing serious," a source told Us in December. "They're having fun and keeping it simple and open. That's it."

Tell Us: Would Kirsten and Garrett make a cute couple?

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