The cast of Avengers: Age of Ultron is already quite large, featuring not only the original superheroes reprising their roles from the first film, but new additions like Quicksilver, Scarlet Witch, and — as confirmed yesterday — Ulysses Klaw. We thought we knew the names of just about everyone involved, but it looks like Joss Whedon’s sequel still has a few casting surprises in store: Linda Cardellini and Julie Delpy have been confirmed for Age of Ultron, but who are they playing?

According to Slashfilm (and confirmed by Disney, so this isn’t an April Fool’s prank), Delpy and Cardellini have been confirmed for Age of Ultron, though their exact roles in the film remain unspecified. It seems unlikely that either actress was cast as Captain Marvel, as Disney and Whedon would both want to keep that information very, very secret until audiences see it for themselves.

Delpy is best known for her role in Richard Linklater’s Before trilogy, while Cardellini recently starred in the Netflix series Bloodline. Both actresses are fantastic, immense talents, so while their appearances in the Avengers sequel may be brief, it stands to reason that Whedon wouldn’t have cast them in unimportant parts. Hopefully.

Delpy and Cardellini are just two more names atop the huge list of stars including the original Avengers cast, along with Anthony Mackie’s Falcon, Tom Hiddleston’s Loki, Idris Elba’s Heimdall, Aaron Taylor-Johnson’s Quicksilver, Elizabeth Olsen’s Scarlet Witch, and a mystery star reportedly making her debut as Captain Marvel. And that’s not even everyone.

Avengers: Age of Ultron opens in theaters on May 1.

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