Gwyneth Paltrow shares what she really thinks about Robert Downey Jr returning to Marvel

Gwyneth Paltrow has shared her thoughts on Robert Downey Jr returning to the Marvel Cinematic Universe (MCU).

Downey Jr's long-running arc in the MCU came to a dramatic end in Avengers: Endgame when Iron Man helped destroy arch-baddie Thanos using the power of the infinity stones.

Of course, the damage from using the stones and the final effort ended up costing Tony Stark his life, bringing the story of one of the original characters in the franchise to a close.

But after his last appearance in 2019's Avengers: Endgame, the actor is now set to make a return to the MCU.

However, Downey Jr will not reprising his role as Iron Man/Tony Stark and instead will be portraying an entirely new character.

This will be as the villainous Dr Doom, the pseudonym of Victor von Doom who is a frequent opponent of the Fantastic Four.

During a surprise appearance at San Diego Comic-Con (SDCC) on Saturday (July 27) the star revealed that he would be taking on the role in Avengers: Doomsday, as well as Avengers: Secret Wars.

After dramatically removing his mask, Downey Jr said: "New mask... same task. What can I tell ya, I like playing complicated characters."

And now Paltrow - who starred alongside Downey Jr in all three Iron Man movies - replied to the actor's post on Instagram announcing the casting.

Robert Downey Jr is set to return to the MCU. (Eric Charbonneau/Getty Images for Warner Bros.)

Referencing how he has shifted from playing the heroic Iron Man to the villainous Dr Doom, she joked: "I don’t get it, are you a baddie now?"

And Paltrow was far from the only MCU alumni to comment on the post.

Mark Ruffalo, who played the Incredible Hulk/Bruce Banner, wrote: "Hey brat, green suits you."

The Russo Brothers also commented, saying: "We've always said green is your colour..."

This is in reference to Dr Doom's look, which is a green cloak and a sinister metallic mask.

At present it's not clear exactly how Dr Doom will be incorporated into the MCU.

There is of course the slight issue of Downey Jr already being synonymous with Tony Stark in the franchise.

While this could be solved by simply having the character never shown without the mask, it could also be another version of Stark from the multiverse, explaining the likeness.

Among those who commented was actor and comedian Seth Green, who reflected the mood by writing simply: "I am entertained."

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