After Will reportedly requested Ellie to speed on "to a faster one so others can join in," he and Kate danced the night away to this classic Grease track. "The Grease number brought the house down," a guest told the Mirror UK. "They stood holding hands in the middle of the dancefloor grinning, then suddenly the opening bars of the song came booming out . . . Will and Kate began dancing around, pointing at each other and mouthing the words. It was hilarious."