WARNING: The following contains spoilers for WandaVision Episode 5, "On a Very Special Episode...," now streaming on Disney+.
With its latest episode touching repeatedly on the subject of death, there was really no better way to give a gut-punch ending to WandaVision's fifth episode than to resurrect Wanda's very own brother, Pietro Maximoff. But with so much out of place and nothing ever being as it seems in this eerie reality, there is plenty of reason to be suspicious. In fact, it's possible that if this new figure isn't Pietro at all, but someone far more sinister.
The theme of resurrection comes up several times throughout Episode 5 in various forms. For starters, S.W.O.R.D. informs their agents that Wanda was last seen breaking into a government facility in order to recover Vision's corpse. Then Wanda and Vision's children, rapidly aging by a power seemingly outside Wanda's control, take in a puppy that passes away during the episode. When her children beg her to bring the puppy back, Wanda treats it as a teachable moment for them. Unfortunately, that lesson may be lost because when she answers the doorbell at the episode's end, she's shocked to see her brother Pietro.
Killed during the events of Age of Ultron where he sacrificed himself to protect Hawkeye and a Sokovian child from gunfire, seeing Pietro living and breathing is somehow not even the weirdest thing about his appearance in WandaVision. As Darcy exclaims from her computer terminal viewing the events Wanda broadcasts, Pietro has even been "recast." In Age of Ultron, Pietro was played by Aaron Taylor-Johnson, but WandaVision sees the character played by Evan Peters, who tackled the role in three of Fox's X-Men movies.
Wanda's grief over her brother has come up in the past, with a reminder of the incident serving as the precursor to Monica Rambeau's banishment from Westview. However, it doesn't make sense for Wanda herself to resurrect him, especially since she needed Vision's body to bring him back and said just before Pietro's arrival that she didn't make the doorbell ring. With no power over her own children and seemingly confused about how she ended up in Westview, there's good reason to believe Wanda isn't alone in manipulating the events of the show.
One of the leading theories is that the force influencing Wanda is the devilish villain Mephisto, known as the Marvel analog to Satan who has his own connections to Scarlet Witch in the comics. Using heroes' loved ones against them and expertly conducting emotional connections like puppet strings is often Mephisto's modus operandi, and during the breakdown of Wanda's reality when she and Vision start to fight, reintroducing a new lost loved one may be the best possible way for Mephisto to keep Wanda inveigled in his spell.
Either way, it's unlikely that Pietro is back for good. Just earlier in the episode, as Monica puzzles over her Kevlar vest rearranged into everyday clothing after entering Wanda's hex, it's revealed that matter isn't created wholly out of anywhere within the realm of Westview. Both Wanda's children and Pietro seem outside her control, unlike anything else around them, and if the reality-bending witch was unstable before, there's no telling what losing her "brother" again could do to her.
Written by Jac Schaeffer and directed by Matt Shakman, WandaVision stars Elizabeth Olsen as Wanda Maximoff/Scarlet Witch, Paul Bettany as Vision, Randall Park as Agent Jimmy Woo, Kat Dennings as Darcy Lewis, Teyonah Parris as Monica Rambeau and Kathryn Hahn as Agnes. New episodes air Fridays on Disney+.