Inside InStyle + HFPA's Star-Studded Bash at the Toronto International Film Festival 

What’s better than a classic little black dress? A velvet and sexy Saint Laurent version with embellishments.

That’s precisely what I, Tonya star Margot Robbie wore on Saturday night to InStyle and Hollywood Foreign Press Association’s annual bash at the Toronto International Film Festival, where she shared one obsession we can’t blame her for: “I have a thing about Saint Laurent dresses, LBD. It’s my fav." What’s a girl to do in a hot designer dress? “I’m gonna go have an espresso martini,” Robbie said, adding, “I need the caffeine hit, but I also would love to have a cocktail.” And she wasn’t the only one looking to raise a glass.

Stars like Nicole Kidman, George Clooney, Elle Fanning, Jake Gyllenhaal, Octavia Spencer, Elisabeth Moss, Evan Rachel Wood, Brie Larson, Jessica Chastain, and James Franco (to name only a few) packed inside the city’s glorious Windsor Arms Hotel for the event. Chastain spent much of the night sipping champagne inside a VIP booth with her Molly’s Game inner circle, while Kate Mara and Emma Roberts caught up like friends that go way back.

Roberts, who stars in Who We Are Now, stepped in wearing a super-short black sheer dress, and was eager to dish tips for walking in heels. "Do anything but fall," she said. "I've almost fallen so many times in heels. I literally lived in New Orleans for five years and I had to just start wearing sneakers and flats 'cause it's cobblestone streets and uneven terrain, and I was like, 'The only way to get around this is to wear flats,' which was a big change for me because at 5'2" I would wear heels all the time, even during the day."

Girl crushes were a topic of discussion inside, with Elisabeth Moss telling us there's only one in her eyes: "It's always Jessica Lange, isn't it?" Speaking of Jessicas, several other actresses like Katherine McNamara (in Rubin Singer) cited Jessica Chastain as the ultimate girl crush—no explanation required. 

When Kidman walked in, crowds parted and she angelically made an entrance in (what else?) a fabulous and equally ethereal Valentino dress. Why’d she choose that number? “Cause I just like it!”

Just as ethereal was Fanning, who not only looked amazing in a blush Alexander McQueen gown, but was truly the life of the party. She was one of the first to arrive and left at around 1 a.m. Earlier in the evening, she told us she’d hope to catch up with her co-stars from The Beguiled, Kidman and Colin Farrell. Just another night for the 19-year-old.

Emma Stone spent over five minutes signing autographs for fans who patiently waited for her outside the venue. Talk about cool? Upon entry, she zipped to her own VIP booth (in a LBD) and met up with Battle of the Sexes co-stars Alan Cumming and Sarah Silverman (in Sarah Flint shoes), who praised Stone for, well, being Emma Stone.

“I’m so impressed with her as a human and as an actress,” Silverman said, adding, “I just love her as a human being and she’s so brilliant. She loves what she does and she never has a crappy moment, you know?”

So how did people feel once inside? “HFPA and InStyle really know how to throw a soiree: great food, great energy, great entertainment,” Octavia Spencer told us after exchanging girl talk with Chastain and Allison Janney. “It’s always a good thing when you get to catch up with old friends, and that’s what it feels like.”

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Scroll down to see all of the stars at InStyle + HFPA’s annual TIFF bash.