Heard the one about Johnny Depp and Amber Heard?

Although Depp, 49, and longtime love Vanessa Paradis announced their split June 19 after 14 years and two children together, the Dark Shadows actor has already moved on -- with his sexy Rum Diary costar Heard, 26.

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"They are 100 percent dating," a source tells the new Us Weekly, out now. "He treats her really well." And how: Another insider confirms a report that Depp recently bought Heard a horse this spring!

After meeting on the set of Rum Diary back in 2009, the duo didn't become romantic until the film's promotional tour in 2011, when Depp and French model-actress Paradis, 39, were already seriously estranged.

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"They started sleeping together during the press tour," a pal says of the bisexual actress, who recently called it quits with girlfriend Tasya van Ree.

PHOTOS: See a seriously goofy pic of Amber!

For much more on Depp and Heard's fledgling romance -- plus another fling with a sexy Pirate of the Caribbean costar, why he and Paradis couldn't make it work, Vanessa's next move, how they'll split their fortune and more -- pick up the new Us Weekly, on stands Friday.

This article originally appeared on Usmagazine.com: Johnny Depp, Amber Heard Are "100 Percent Dating"