Harry Styles surprised fans during his 'Harryween' tour show in Los Angeles, by dressing up as Grease's Danny Zuko and performing hits from the film.
Wearing a leather jacket, black trousers and a black, slicked-back wig, the singer performed ballad, 'Hopelessly Devoted To You'.
Girlfriend, Olivia Wilde, was also in attendance dressed up as a bunny.
Last year's Harryween took place at Madison Square Garden in New York, where the 28-year-old donned a ragdoll costume.
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