"What If... The Avengers Assembled In 1602?" has been one of What If...? season 2's most highly anticipated episodes and it's fair to say it doesn't disappoint. It is, however, just as different from the comics as the first season's take on Marvel Zombies!
We begin with Loki performing Shakespeare on stage, only for a rift to open above the performance which pulls Hela into it. While Captain Carter - who was transported to this reality by Wanda Merlin and Sir Fury - saves the God of Mischief, she's unable to rescue Hela and an incensed Thor is named King.
The Scarlet Witch summoned Peggy Carter there to help stop these rifts, and the hero is forced to go on the run after the God of Thunder blames her for failing to achieve the mission she was tasked with.
We learn from The Watcher that this timeline is dying and that some worlds are meant to blink out of existence; as he points out, he's seen it happen to millions of them. It's unclear whether this is a result of incursions or the Multiverse instability, but this is a broken world where 1602 and the modern Avengers have been mashed up when their respective realities collided; that sounds like an incursion to us.
Peggy refuses The Watcher's offer to be taken home and figures out with the help of Tony Stark that there must have been a "forerunner" - a being from a different world - whose presence in 1602 has caused realities to collide and merge.
The hero later meets Rogers Hood and his Merry Men, Ant-Man and Bucky Barnes. Steve vows to help Peggy steal King Thor's sceptre to power a device Tony is working on, but it's then the shrinking Royal Yellowjackets attack under the orders of Sir Harold "The Happy" Hogan. The Destroyer is unleashed and Captain Carter is imprisoned.
The Watcher once again comes to her and offers to take her home, but she mocks his many "What If...?" questions and instead frees The Hulk and escapes. The heroes attack Thor's palace and The Hulk squares off with Happy who has now transformed into "The Freak."
Peggy, meanwhile, takes on Thor and his "All-Father" Vibranium sword but after nabbing the sceptre, we learn Steve Rogers is the forerunner. In his reality, he inadvertently hit Thanos' Time Stone with his shield during Avengers: Infinity War's battle in Wakanda, leaving him stranded in the past. He wipes himself out of existence before a distraught Peggy and the timeline corrects itself and is saved.
Now stranded, the World War II looks up to find Supreme Strange staring back at her! To be continued...
In terms of familiar voices, this episode of What If...? is star-studded, with Hayley Atwell as Captain Carter, Samuel L. Jackson as Sir Fury, Elizabeth Olsen as Wanda Merkin, Chris Hemsworth as King Thor Odinson, Tom Hiddleston as Loki, Mark Ruffalo as The Hulk, Jon Favreau as Happy, Paul Rudd as Ant-Man, Sebastian Stan as Bucky, and Benedict Cumberbatch as Doctor Strange.
Once again, the only recast roles were Tony Stark (Mick Wingert), Steve Rogers (Josh Keaton), and Black Widow (Lake Bell).