How Britney Spears and Paris Hilton Influenced 'Promising Young Woman' (Exclusive)

ET spoke with ‘Promising Young Woman’ director Emerald Fennell and star Carey Mulligan ahead of the film’s release, in theaters Christmas Day. Between the ‘Stars are Blind’ dance number and the ‘Toxic’ string quartet, it’s clear Paris Hilton, Britney Spears and more pop hits were large influences on the upcoming flick. Mulligan and Fennell break down the inspiration, costumes and more!