Watch Harry Styles sing Grease's 'Hopelessly Devoted to You' dressed as Danny Zuko at his Harryween concert

"Did you dress up for Halloween?" Because Harry Styles sure did.

The My Policeman star traded in his uniform for a sweet leather jacket, black jeans, and a slicked back hairstyle as he transformed into Danny Zuko from Grease as part of his annual "Harryween" concert celebration. The "Watermelon Sugar" singer's ensemble played homage to Danny's final outfit in the 1978 movie musical, but with its own twist: both Harry's leather jacket and black, studded were both emblazoned with the word 'Harryween' in sparkling red gems on the back.

Styles did more than just dress the part of the beloved greaser (played onscreen by John Travolta) on Monday night. He also led the sold-out Kia Forum crowd in a spirited rendition of Olivia Newton-John's hit "Hopelessly Devoted to You" from the film. Images of Newton-John, who died in August, were also shown on an overhead screen.

Throughout the evening, Styles played into the part of Danny by throwing in a few Grease references to his performance too, including slicking back his hair during "Satellite," doing some finger guns in the middle of "Daydream," and performing the Hand Jive in "Adore You."

But he wasn't the only one dressed up for the holiday. Styles' band also joined in on the fun with their own Grease-inspired outfits. Drummer Sarah Jones donned Sandy's iconic black spandex ensemble; bassist Elin Sandberg was Rizzo; instrumentalist Ny Oh was Frenchie; guitarist Mitch Rowland was Coach Calhoun; keyboardist Yaffra was Eugene Felsnic; and percussionist Pauli Lovejoy was a Pink Lady.

Harryween has become a tradition for Styles, who performed two Halloween-themed shows in New York City's Madison Square Garden last year. On the first night, he and his entire band dressed as characters from The Wizard of Oz, with Styles starring as Dorothy and singing "Somewhere Over the Rainbow."

On the second evening, Styles donned a Pierrot clown costume, designed by Gucci, and performed a knockout cover of Britney Spears' "Toxic."

Sign up for Entertainment Weekly's free daily newsletter to get breaking TV news, exclusive first looks, recaps, reviews, interviews with your favorite stars, and more.

Related content:

• Watch Emma Corrin and Harry Styles in exclusive clip from My Policeman pool scene
• The cast of Grease: Where are they now?
• Watch Harry Styles' full X Factor UK audition with previously-unseen 'Hey, Soul Sister' performance