Scarlett Johansson, The AvengersAlberto E. Rodriguez/WireImage

Scarlett Johansson channeled her sexy assassin character Black Widow in a tight Versace dress at last night’s Hollywood premiere of The Avengers, where she caught up with co-star Cobie Smulders (in Donna Karan). Of the sexy catsuit she wore in the movie, Johansson said the design had to be as functional as it was provocative. “There’s a lot of bending and sliding and rolling and all that stuff,” she said. “The suit’s got to be tough!” Catch The Avengers in theaters May 4th, and see more stars at last night’s hottest parties in the gallery now.

— Leah Abrahams, with reporting by Lindzi Scharf