Last month, The Falcon and The Winter Soldier showrunner Malcolm Spellman sent the internet into a frenzy when he revealed that episode five would feature a surprise cameo from "a very, very grounded character" with a "strong" personality, who he would like to see "partnered with one of the big world-shakers like Thor."
That doesn't sound like Mephisto, but after those big WandaVision teases didn't pay off, fans are approaching next week's instalment of the Disney+ series with some serious trepidation.
Now, /Film has shared some exclusive details on what to expect.
The site reveals that "this surprise character is not one that we’ve seen in the MCU before and not one who is primed to appear in an upcoming film. However, we have learned it is an existing Marvel Comics character who is played by a well-known performer."
So, it's a character from the comic books, played by a familiar face. Honestly, that doesn't really narrow things down!
We could be talking about a Power Broker reveal here, or something as simple as a big name star playing a relatively obscure character from the source material who could suit up down the line. Plus, just because they're not set to appear in an upcoming movie, that doesn't mean they won't be in an upcoming TV show!
Our best guess is Tatiana Maslany as Jennifer Walters, but we'd love to hear your theories in the usual place!