WandaVision Episode 5 has shocked Marvel fans with its major twist ending, which brought a franchise-shattering cameo to the Marvel Cinematic Universe. (Major Spoilers!) Just when it looked like Wanda (Elizabeth Olsen) and Vision (Paul Bettany) were finally set to clash over Wanda's faux reality bubble, a knock on the door arrived just in time to break-up the tension. However, the relief was short-lived: the visitor turned out to be Evan Peters' Quicksilver from the X-Men movies franchise! Peters introduces himself as Wanda's "long-lost brother, Pietro," but Wanda looks confused at the sight of him. Is that really Pietro standing in Wanda's doorway?