Lots to catch up on!

They're two of this year's most talked-about Hollywood women, and at Wednesday night's star-studded 12-12-12: A Concert for Sandy Relief at NYC's Madison Square Garden, Katie Holmes and Blake Lively** encountered one another backstage.

Recently divorced from Tom Cruise, 33-year-old Holmes appeared for the charity event in one of her sexiest looks to date: A curve-hugging purple velvet dress by Tom Ford featuring daring panels, plus "Padlock" pump by the same designer. Currently starring in Broadway comedy Dead Accounts, the mom to 6-year-old Suri wore her brunette locks down in loose waves.

25-year-old Lively, meanwhile, lent her support at the event in one of her first major events since she wed Ryan Reynolds** in a surprise, top-secret bash back in September. The fashionista wore a tight, studded red leather mini-dress by Isabel Marant and nude caged ankle boots by Christian Louboutin.

Just a few nights ago, former Dawson's Creek star Holmes celebrated the holiday season at Broadway Dreams Foundation's Champagne and Caroling gala -- where she was spotted "double-fisting champagne in one hand with a Diet Coke in one hand with a Diet Coke in the other."

Lively, whose Gossip Girl airs its last-ever episode next Tuesday Dec. 18, has been keeping an especially low profile since since and Reynolds, 36, tied the knot. The blissed-out couple were photographed packing on the PDA Dec. 3 on the Pont des Arts bridge in Paris.

"The locals said hello, but they were only interested in each other," an eyewitness told Us.

This article originally appeared on Usmagazine.com: Katie Holmes, Blake Lively Look Sexy, Bond at 12-12-12 Concert