1 | Doc Sampson (Ty Burrell), The Incredible Hulk

Before Modern Family made him a household name, Ty Burrell appeared as superhero psychiatrist Doc Sampson in 2008’s The Incredible Hulk. Whatever plans may have been in place for the character to return appear to have been jettisoned alongside Edward Norton’s incarnation of the titular angry green hero. Mark Ruffalo took over the role for 2011’s Avengers, and Sampson has been MIA ever since.

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2 | Aaron Davis (Donald Glover), Spider-Man: Homecoming

Aaron Davis, in the guise of his alter-ego the Prowler, is one of the primary antagonists of Miles Morales/Spider-Man in the animated Spider-Verse films, but his live-action counterpart hasn’t been given nearly as much to do. Donald Glover (who is said to have actually inspired the creation of Miles Morales in the comics) appears as Prowler in 2017’s Spider-Man: Homecoming, but only for a single scene, facing off against Tom Holland’s Peter Parker. Other than a brief cameo in 2023’s otherwise animated Spider-Man: Across the Spider-Verse, Glover’s version of Aaron Davis hasn’t appeared on the big screen since.

3 | W’Kabi (Daniel Kaluuya), Black Panther

Daniel Kaluuya was an Oscar nominee but not yet a winner when he appeared in 2018’s Black Panther as W’Kabi, a once-loyal second-in-command who betrays Chadwick Boseman’s King T’challa, believing he’s doing what’s best for Wakanda. But despite his character surviving to the end of the first film, Kaluuya didn’t appear in Black Panther 2: Wakanda Forever because he was filming Jordan Peele’sNope. Given Boseman’s untimely passing in 2020, it seems unlikely the MCU will circle back to the fate of W’Kabi.

4 | Eros (Harry Styles), Eternals

Superhero movies tend to favor their iconic characters over the stars who portray them, but not even the MCU could resist the chance to cast one of the world’s biggest pop stars. In a mid-credits scene at the end of 2021’s Eternals, Harry Styles makes his debut as Eros, aka Starfox, the brother of the mega-villain Thanos. Seems like he’d have a bone to pick with Earth’s heroes, but we might never see him again onscreen—Marvel movie boss Kevin Feige admitted there are no solid plans at this point, and all the rumors suggest Eternals 2 isn’t happening.

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5 | Dane Whitman/Black Knight (Kit Harington), Eternals

Eros wasn’t the only deadend resulting from an Eternals mid-credit scene. In another, Kit Harington’s Dane Whitman discovers a magical sword as we hear the voice of Mahershala Ali’s Blade asking him if he’s ready. Comic book readers know this heralded Whitman’s transformation into the Black Knight—but we’ll probably never get to see what happens next, as the actor said he won’t appear in 2025’s Blade, which has been plagued with issues.

6 | Hercules (Brett Goldstein), Thor: Love & Thunder

A mid-credits scene at the tail end of the fourth Thor film, 2022’s Thor: Love & Thunder, seemed to promise a future face-off between the God of Thunder and the legendary Hercules, played by Ted Lasso’s Brett Goldstein. However, given writer/director Takia Waititi’slikely departure from the MCU and star Chris Hemsworth’s calls for Thor 5 to be “unpredictable,” it’s questionable whether that battle will ever come to pass.