The first news of original Marvel content appearing on Disney+ dropped in September 2018, when Variety reported Marvel was busy developing limited series for Disney's streaming service.

Details were scarce in that first report, but what little we learned has since been confirmed. Variety singled out Loki (Tom Hiddleston) and Scarlet Witch (Elizabeth Olsen) as two Marvel characters set to get their own series on Disney+. They reported each series would be between "six to eight episodes" long and that the budgets for each series would be "hefty rivaling those of a major studio production." Marvel Studios president Kevin Feige was reported to be directly involved in the shows' developments, and the original actors were set to reprise their roles.

While the article makes it clear Marvel planned for other series, the fact that Loki and Scarlet Witch were the first named characters to be involved was curious. Both characters were killed five months earlier in Avengers: Infinity War. The nature of Scarlet Witch's death led most to correctly believe that she — along with other Marvel heroes already with confirmed post-Infinity War films like Spider-Man (Tom Holland) and Black Panther (Chadwick Boseman) — would be resurrected in the follow-up. But Loki was killed, seemingly, with much more brutal finality — his neck broken by Thanos (Josh Brolin), leading some to believe the Loki limited series either was a prequel or that its announcement spoiled the character's resurrection in Avengers: Endgame. Surprisingly, both guesses would be proven wrong.