’Tis the season! Joe Manganiello, Armie Hammer, Ashlee Simpson Ross and more stepped out to spread the cheer at producer Jennifer Klein’s annual holiday party in L.A. on Saturday, December 3, and Us Weekly has the star-studded details from inside the fête.

According to a source, some of the earliest arrivals included Lily Collins and Alexandra Daddario, who chatted while the Baywatch actress sipped on Chloe wine in the living room. Soon after, Scott Speedman arrived and grabbed a Don Julio holiday cocktail at the bar outside before finding a corner to catch up with Len Wiseman.

Manganiello arrived sans wife Sofia Vergara. He drank Health-Ade Kombucha and snacked on Sidecar Doughnuts while mingling in a quiet corner.

Hammer and Elizabeth Chambers also showed up to celebrate the season. Chambers, who is pregnant with the couple’s second child, sipped on Icelandic Glacial water over ice and gushed about her soon-to-be baby boy, whom she was pleased to say will be a Capricorn.

Later, the source notes that Hammer snagged some Edward Marc Snappers and followed his wife to the back patio, where Bryce Dallas Howard — enjoying Freixenet Cava sparking wine — caught up with Topher Grace on one of the couches.

Across the patio, Simpson Ross and husband Evan Ross completed a lap around the party, stopping to grab some barkTHINS from the chocolate bar, which was also stocked with Hershey’s Cookie Layer Crunch, macarons and mini cupcakes from Baked By Melissa, Jo’s Candies and Lily’s Sweets. Taye Diggs was also feeling the snack vibes as he dug into the tins of Garrett Popcorn.

Gilmore Girls fan favorite and This Is Us star Milo Ventimiglia arrived in style in a Cadillac and mingled throughout the party, passing Maria Menounos in the entryway, who was holed there excitedly talking with Dane Cook. Meanwhile, Gugu Mbatha-Raw fueled up with Don Julio mini margaritas and Jeni’s ice cream before dancing the night away like the diva queen she deserves to be.

Before heading home for the evening, Matt Leinart took a Megpie to bring home to his son, Cole, and Tia Mowry hit up the Chipotle build-your-own buffet with husband Cory Hardrict.

Other notable guests included Allison Janney, Michelle Monaghan, Charlie Weber and Katie Lowes, who were also able to indulge in hot chocolate and coffee from The Coffee Bean & Tea Leaf, Suja juice, Cookie Chips, classic Hostess treats, Sprinkles cupcakes and cookies, Pasta Chips and savory bites from ShopHouse.

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