Jolie on red carpet for first time since double mastectomy

(CNN) -- There was one star who stole the show at a London movie premier. Angelina Jolie stepped out onto the red carpet for the first time since revealing she underwent a double mastectomy.

With longtime partner Brad Pitt at her side, Jolie attended the London premiere of World War Z, starring Pitt.

"To be through it, to be on the other side. For her to be healthy and for that thing not to be the thing that takes her is everything to me," Pitt said.

Last month, the actress wrote an op-ed piece disclosing she'd tested positive for the gene mutation linked to breast and ovarian cancer, and decided to undergo the preventative procedure.