Rumlow was a main villain in 2014 movie Captain America: The Winter Soldier and made a return in 2016’s Captain America: Civil War where he met his untimely end. He also made a cameo in Avengers Endgame when Steve travelled back in time.
Revealing what he could talk about in the show, Grillo said: “I can tell you absolutely nothing!
“You know what I’m going to tell you… I can tell you I just did another episode and the quality – and this is the great thing about Marvel – the quality of the scripts… it’s just the best of the best of the best. And that’s why they’re so successful.”
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He said: “I don’t know the number. But as they kind of finish them we find out then if we’re going to be in that one.”
Considering Rumlow played a large part in two of the Captain America films, it would make sense to see the villain make a return in a large portion of the series.
Although his character died in 2016, Grillo has secretly been recording lines for the show for the past year during the coronavirus pandemic.
“I’ve known Chadwick for a good seven or eight years. I mean… superstar talent. Would have had an amazing, beautiful, eloquent career.
“And, you know, he changed the game. He was really a special actor, a special man.”
The 55-year-old actor also touched upon working in close-quarters with Evans during the iconic elevator fight scene in The Winter Soldier.
“When we left that elevator… we didn’t leave anything in the elevator I’ll tell you that much. We were black and blue and sore. And, you know, we beat each other up!”
He also added: “I still consider it Marvel’s best movie. I consider Winter Soldier the best all-around film.”
What If…? is due out this year on Disney Plus.
The Captain America films are available on Disney Plus now.
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