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

Anya Taylor-Joy stars in 'Dune: Part Two' as a surprise role.

It has been revealed today at the London premiere of 'Dune: Part Two' that Anya Taylor-Joy will star in the film as a surprise role. The role is revealed to be a major character from the franchise. 

When asked about the film, Taylor-Joy shares that it is "one of the best movie she has ever seen in her life".