The New Queen of Halloween! See All the Photos from Demi Lovato's Spooky It-Themed Party

On Saturday night, Demi Lovato threw an epic Halloween party at SBE's Hyde for her friends and family.

"She threw the party because she was inspired by the It sequel and had never dressed up as Pennywise," says a source close to the star. "The full look took about three hours to complete!"

Fully committing to the theme, the star transformed Hyde's entrance into a clown maze complete with stilt walkers and characters jumping out to scare her guests.

Paris Hilton completed her school-girl uniform with pigtails.

YouTuber Nikita Dragun dressed up as an anime character. "i bet y’all never seen a bitch ninja run in 8 inch heels," she wrote on Instagram.

Meanwhile, Travis Barker fit right in with a clown get-up.

Draped in pearls, Kate Beckinsale looked chic while channeling Audrey Hepburn in Breakfast at Tiffany's.

Jameela Jamil cozied up to Lovato in her nun outfit.

Expecting her first child, Ashley Graham (with husband Justin Ervin) looked sultry as ever dressed up as Jessica Rabbit. "Macho Man knocked up Jessica Rabbit for Halloween," she wrote on Instagram.

Singer Ally Brooke — dressed as Cat Woman — reunited with Lovato at the bash.

To keep her guests happy and full, Lovato served Umami Burger sliders and two kinds of fries.

Guests also stayed hydrated with Fiji Water and tucked into a Sugar Factory candy bar stocked with festive Halloween gummies and candy corn.