There were already dozens of Avengers: Endgame secrets and Easter Eggs for fans to enjoy, but the list just keeps on growing. Now, it's been revealed that Tony and Steve's trip through time actually crossed paths with Hydra years before they betrayed S.H.I.E.L.D.--but there's no way they, or the audience, would ever have noticed.

The final entry in the MCU's Infinity Saga found a way to pay tribute to almost every movie that came before. And even if fans couldn't actually explain how or why Red Skull guarded the Soul Stone, the inclusion of Captain America's villain was a pleasant surprise. But it turns out there is another connection made between Endgame and the Red Skull's legacy, visible during the movie's trip back in time to 1970. That isn't figurative, either: fans can literally see the man who will lead to Hydra's return, and the death of S.H.I.E.L.D. years later. They just didn't know what they were looking at, until now.

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The new Easter Egg is dropped after Tony Stark and Steve Rogers travel to Camp Lehigh in 1970, and successfully infiltrate the early S.H.I.E.L.D. installation below ground. As Steve searches for a batch of Pym Particles, Tony goes even deeper to take the Tesseract off his father's hands. Now thanks to an effects reel from VFX studio Cinesite, responsible for creating the environment Tony navigates (among others), fans can confirm the lab in question is likely the same one visited by Steve and Nat in Captain America: The Winter Soldier. Including its villainous, artificial inhabitant...

Avengers Endgame Easter Egg Arnim Zola Hydra

The small screen of green static visible throughout the scene--both before and after Howard Stark interrupts--may throw viewers off the scent. But it's the cluster of monitors visible in the background when Tony first enters that should be focused on, instead. Especially now that the VFX team confirms the crackling black and green images are the face of Arnim Zola (in an earlier form of his computerized, 'immortal' evolution). A form that only Steve Rogers would have recognized, meaning Tony had even less of a chance of spotting the telltale Zola than the viewers. The version of Zola (played by actor Toby Jones) is actually easier to make out. But it's also placed so far out of focus, fans will have to wonder if Marvel Studios was even aware of the Easter Egg, or if it's simply an homage placed by the VFX artists themselves.

Since Endgame directors Anthony and Joe Russo were also responsible for the Zola/Hydra/S.H.I.E.L.D. reveal in this same location in Captain America: The Winter Soldier, it seems equally likely that they personally inserted the Zola monitors to establish continuity. Either way, it's a terrific and almost impossible to catch detail that might never have been found without the culprits' confirmation. Which means Marvel fans can add it to their Easter Egg lists as they rewatch Avengers: Endgame, waiting for Marvel's next superhero movies to arrive in theaters.

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Source: Cinesite

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