Robert Downey Jr’s Highest-Rated Movie Is Huge News For One MCU Reunion

Published Sep 21, 2026, 12:45 PM EDT

Zoë Miskelly is an editor and second in command for Screen Rant's Movies team, having covered the entertainment industry for almost 10 years now. Zoë's love of superheroes and all things Marvel & DC started out in childhood, and has blossomed into a career getting to talk about some of the biggest and best movies and shows of all time, having previously focused on comics while working at WhatCulture.

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Robert Downey Jr's highest-rated movie on Rotten Tomatoes bodes well for one film reunion that's teed up to take place in the next segment of the MCU. As the face of the MCU for much of its history, Robert Downey Jr's stardom rose immensely throughout the course of Iron Man's on-screen story, with the character still being one of the first figures people think of when they picture the billions-grossing franchise.

This appears to have at least partly played a role in the actor's return to the MCU as Doctor Doom, which has already drawn much audience interest and curiosity in terms of how this choice will fully play out on-screen. What that said, though Avengers: Doomsday is clearly due to center on Doctor Doom in a major way, he's by no means the only major figure set to appear in the movie.

Indeed, it's the wider cast of Avengers: Doomsday that bodes best for the movie and its story, especially because of the talented assortment of actors within its ranks. This includes one actor who was the central figure of Robert Downey Jr's highest rated movie by critics on Rotten Tomatoes, making the prospect of the two reuniting once more in another movie's cast all the more interesting.

Robert Downey Jr's Highest-Rated Movie On Rotten Tomatoes Starring Ian McKellen Bodes Well For The Pair Appearing In Avengers: Doomsday

While Robert Downey Jr's time as Tony Stark in the MCU is one of his most famous roles by a fair margin, it's interesting to note that none of his collective appearances in the MCU's various films top his filmography in terms of their reviews from critics on Rotten Tomatoes. This is impressive by itself, as Avengers: Endgame holds a decidedly respectable 94% Tomatometer rating, and the original 2008 Iron Man movie that started it all also has the same score.

Instead, the actor's list is topped by two non-superhero films, with second place going to 1993's Short Cuts - which has a 95% rating - and first place going to 1995's Richard III, which has a 96% rating.

Richard III is notably star-studded in that Robert Downey Jr. is by far the only recognizable name in its cast, with the movie being helmed by Ian McKellen, who plays the role of the titular King Richard III, and also featuring Dame Maggie Smith. The acting caliber of this crew goes some way to explain its high review score, but also tees up the MCU's next steps to be particularly exciting as well, since both Robert Downey Jr. and Ian McKellen will be appearing in the cast of the franchise's next chapter.

Doctor Doom & Magneto Returning In The Same MCU Movie Has Potential To Create One Of The Superhero Genre's Best Live-Action Fights

Avengers: Doomsday has a considerable cast, but two of the most long-tenured and much-praised actors within it are of course that of Robert Downey Jr - who will be appearing as Doctor Doom following his debut in The Fantastic Four: First Steps - and Ian McKellen, who will be reprising his role as Magneto following his time as the character previously during many of Fox's X-Men films.

This is promising in terms of the acting talents on display in the upcoming MCU movie, but is also further promising in terms of the power level of these two characters as well, since Doom and Magneto are often in the higher echelons of heroes and villains thanks to their respective abilities and the clever ways they're able to use them.

As such, not only are Robert Downey Jr. and Ian McKellen both likely to be on top form in Avengers: Doomsday, the prospect of them appearing on-screen together looks as though it would be paired nicely with a truly dramatic action sequence as well, since the potential of seeing Doom's magical prowess go up against Magneto's immense magnetic powers does seem like one that the MCU would be foolish to not follow up on.

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  Victor von Doom

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  Reed Richards / Mr. Fantastic

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  Thor

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  Vanessa Kirby

  Sue Storm / Invisible Woman

Avengers: Doomsday is the fifth Avengers film and kicks off Phase 6 of the Marvel Cinematic Universe. A stacked cast of heroes both new and old to the MCU — including members of the X-Men — will face off against Victor von Doom, revealed at San Diego Comic-Con in 2024 to be played by a returning Robert Downey Jr.