Reid opted to celebrate two holidays in one, rocking a Christmas-inspired get-up, complete with a furry Christmas hat. We're guessing this is what Mrs. Claus would wear on vacation (or Spring Break): the red tube top and skirt were lined with silver sequins, and the mini was also covered in white feathers along the hem. She completed her look with a black bag and clear wedges.
The American Pie alum was far from the only one rocking sexy costumes at the soiree, sponsored by Abosult Elyx. Joanna Krupa showed off nearly everything as a dominatrix. Her look included a completely sheer bodysuit that featured black tape over her nipples, studs along the shoulders and hips, and spiked cuffs, plus she accessorized with a choker, thigh-high black boots, and, of course, a whip. She finished her look with heavy makeup and a sky-high raven ponytail.
Leona Lewis, on the other hand, was covered head-to-toe in gold bodypaint that perfectly matched her dazzling, curve-hugging gown, which gave the overall feel of an Oscar statuette.
Leonardo DiCaprio, The Weeknd, Gerard Butler, Taylor Lautner, Emile Hirsch, Josh Hutcherson and new father DJ Khaled were also among the celebrities at the Halloween fête.
Reid has been back at work on a new movie, Worthless, filming in her native New Jersey. Last month, she scared fans, however, when she posted a photo of her face covered in bruises, but thankfully, they were just for the project.
ET sat down with Reid last February, when she candidly shared how negative comments about her body has affected her.
"I'm a human. If you cut me I bleed," she said. "I'm just like everyone else. I think that when people are famous, they don't realize that they are actually human."
Hear more from the Sharknado star in the video below.