coup de main - noun
kü-də-ˈmaⁿ
Definition of coup de main : an attack that achieves complete surprise.

Watch: Julia Michaels and Niall Horan perform 'What A Time' together live on The Late Late Show.

Julia Michaels and Niall Horan appeared on The Late Late Show with James Corden last night to perform their duet 'What A Time' together live, after puzzling their way out of an escape room game... just in time.

Watch the performance below...