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

Watch: Taylor Swift and Aaron Dessner perform 'The Great War' and 'Mad Woman' live.

Taylor Swift brought out Aaron Dessner as a special guest in Tampa, Florida last week - performing 'The Great War' and 'Mad Woman' together live for the very first time.

Watch clips of both performances below...