Robert Downey Jr., Gwyneth Paltrow, and Jon Favreau were there for the beginning of the Marvel Cinematic Universe in 2008, so it’s only appropriate that 10 years later, they’re front and center for its grand finale. The Iron Man architects — who previously reunited for a surprise cameo in this summer’s hit Spider-Man: Homecoming — are together again on the set of the fourth Avengers film as their Marvel-ous alter egos Tony Stark (is that a new arc reactor on his chest?), Pepper Potts, and Happy Hogan, respectively.

While they’re all smiles in the above photo — which Favreau shared on his Twitter feed and Downey posted to his Instagram — hard times are likely in store for the self-described “Infinity Trinity.” That’s because the fourth Avengers film, set for release in 2019 (and shooting back to back with the just-wrapped Avengers: Infinity War), promises major changes to the MCU as we know it, with Marvel Studios head honcho Kevin Feige even telling the press that the “22-movie arc” that Favreau kicked off in the original Iron Man will come to an end in that still-untitled team-up picture.

But if our “Infinity Trinity” — or any of their super pals — are going out, at least they’re going out with a bang. The Avengers 4 set has been a hotbed of fan-friendly tomfoolery, including this widely shared shot of onscreen “Science Bros” Downey and Mark “Bruce Banner” Ruffalo kissing and making up after that whole “Hulkbuster” fight in Age of Ultron.

Meanwhile, newly engaged power couple Pepper and Tony were photographed laughing it up during on-set rehearsals. As hawk-eyed fans might notice, Paltrow is also sporting a giant rock on her ring finger that could be part of her character’s accessories. Better make sure it’s not an Infinity Gem. …

Watch this real-life Avengers fight caught on our cameras:

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