There are major SPOILERS for Infinity War below, so read ahead at your own risk. Aaron Taylor-Johnson was spotted in Atlanta on the set of Avengers 4. After the events of Infinity War, it appears Quicksilver may be returning to the fold. The character was first introduced in Age of Ultron and killed off to help the story arc of his sister, Wanda. Plus, Joss Whedon, who directed the movie, has a fondness of introducing characters and then killing them off. But it seems that Quicksilver will make a quick return in Avengers 4.

The set photos from Avengers 4 have hinted that time travel and the Quantum Realm will have a large impact on the story. If the time travel, or even alternate universe theory, end up as true, it seems highly likely that Quicksilver will make an appearance in the upcoming movie. Additionally, the spotting of Aaron Taylor-Johnson on the set pretty much guarantees that the character will return. However, he may only return for a cameo in a flashback sequence.

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If that wasn't enough, Aaron Taylor-Johnson was spotted on the set at the same time as Tom Hiddleston's Loki, who obviously died at the beginning of Infinity War. Quicksilver and Loki could exist in an alternate universe type of scenario or time traveling, but the latter seems like it would bring up some trouble for Loki, since he was the villain in the first Avengers film. Some of the leaked images from the set of Avengers 4 have shown Tony Stark, Thor, Hulk, and Captain America in their original suits from the first movie, which has fueled the time travel theories.

There are plenty of theories and speculation surrounding Avengers 4, but the Russo Brothers as well as screenwriters Stephen McFeely and Christopher Markus have promised that the movie will be completely unexpected. This could all be deflection from the leaking of spoilers, but the team was able to pull off many shocking surprises for Infinity War that not even the most diehard Marvel Cinematic Universe fan saw coming. It will be interesting to see if Marvel Studios is able to keep the level of secrecy going for Avengers 4 with nearly a year left to go .

Aaron Taylor-Johnson was spotted on the set of Avengers 4, so how will Quicksilver factor into the overall story? That remains the mystery at this point. Time travel has to be the reasoning unless the movie is going to deal with the overuse of flashbacks, which seems like a huge step backwards for the MCU. Again, there's still a year to go, and reshoots for Avengers 4 are expected to occur this fall, so maybe some more pictures will leak out, shedding some more light on the mysterious plot. For now, there's plenty to unpack from the events of Infinity War for MCU fans. This report originated from Express U.K.