Over the course of more than 15 years of film and television shows, the Marvel Cinematic Universe has grown to contain a veritable galaxy of Hollywood stars. Some of those stars have appeared in upwards of half a dozen movies and series as their characters, until they become nearly synonymous with their onscreen Marvel roles. It’s hard to think of Robert Downey Jr. at this point, for example, without conjuring an image of him in that Iron Man armor.

That’s one side of an actor’s life in the MCU. The other: When a famous actor is brought in for a smaller role in one project that never turns into an ongoing multi-franchise part. In fact, some of the biggest stars to ever appear in Marvel movies only made one-off appearances. (The more successful the actor, the harder it is to get them to sign one of Marvel’s restrictive long-term contracts.) At this point, so many movie stars have swung through the MCU that it’s hard to keep track of them all — and easy to forget some of the familiar face who’ve taken part in this massive franchise.

Below, I’ve collected 20 of the most notable examples of actors whose Marvel appearances have mostly faded from memory. But there are many more where these came from; these are just actors from MCU’s so-called Infinity Saga, when Marvel’s output was limited to one or two movies a year. These days, the studio cranks out two movies every year plus two or three Disney+ series every 12 months — and all of that content needs good actors to keep it grounded and plausible and emotionally compelling. Just like the real universe, the MCU never stops expanding.

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