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

Watch: Taylor Swift and Idina Menzel perform 'Let It Go'.

| by Shahlin Graves

Taylor Swift spent her Halloween this year in an Olaf [the Snowman] costume, performing 'Let It Go' live as a duet with Idina Menzel on the 1989 World Tour in Tampa, Florida.

Watch the performance below...