The English hunk, 38, and Bosworth, 32 — who was joined by her husband, director Michael Polish — posed for photos and shared a laugh together at the star-studded event. Bloom wore a leather jacket and gray pants. Bosworth donned a black dress and added a pop of red lipstick.
Bloom and the Life on the Line actress previously bumped into each other at the Hammer Museum's 12th Annual Gala in October 2014. At the time, Bloom and Polish looked like old friends catching up.
Bloom and Bosworth broke up in 2006 after more than two years of dating. Bosworth went on to marry Polish in a romantic outdoor ceremony in Montana in August 2013. Bloom ended his three-year marriage to model Miranda Kerr in October 2013; the exes share 4-year-old son Flynn.
Despite their happy run-in Thursday, Bosworth had a tough time after she and Bloom ended their relationship. She opened up about the heartbreak during an interview with Sunday Times Styles in October 2011.
"You know when you put all your chips into something, then it disappears? The [split] sent me into such pain, I think I had actual vertigo. I was like, 'Is this my new reality? Will anything be normal again?'" she said at the time. "Then one day you wake up and you think, 'Okay, I'll never be the same, but I'll survive and I'll grow from it.'"
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