Fans are still reeling from the devastating deaths of Avengers: Infinity War. Could there be hope that a dead Marvel Universe character will return in the sequel?

Potential spoilers follow.

According to reports, actor Aaron Taylor-Johnson has been spotted on the set where the filming of Avengers 4 is taking place.

Taylor-Johnson played Pietro Maximoff, aka Quicksilver in Avengers: Age of Ultron. He and his sister Wanda, aka the Scarlet Witch (Elizabeth Olsen) were transformed into superpowered beings after Hydra leader Baron Wolfgang von Strucker experimented on them using Loki’s scepter, now known to have contained the Mind Stone. Wanda gained psychic and telekinetic abilities and Pietro gained super speed.

At first, Quicksilver and the Scarlet Witch were pawns of Hydra and then worked with Ultron. Eventually, they turned on Ultron and joined up with the Avengers during the Battle of Sokovia. Quicksilver gave his life using his super speed to shield Hawkeye from oncoming fire.

So how does Quicksilver return in Avengers 4, if he is going to return at all? One theory is that whatever the Avengers do to reverse the effects of Thanos’s finger snap brings back more than just the 50 percent of all life that perished in Avengers: Infinity War. However, that would probably cause a whole set of new problems.

The more likely scenario is that Avengers 4 involves time travel. This theory is backed by a few things. Ant-Man and the Wasp and Captain Marvel, the two Marvel Studios films releasing between Avengers: Infinity War and Avengers 4, both take place before the events of Avengers: Infinity War, possibly setting up points of reference for time travel in Avengers 4.

There are also further rumors from the set of Avengers 4. Tom Hiddleston was reportedly spotted on the Avengers 4 set in costume as Loki despite his character having died by Thanos’ hand in Avengers: Infinity War. There have also been set photos of the core Avengers cast with looks like the ones they wore in the first Avengers film. This information could be evidence of flashback scenes rather than time travel, but the case for time travel seems to be building.

The fourth Avengers movie, which remains untitled, opens on May 3, 2019.

Avengers: Infinity War is now playing in theaters. Other upcoming Marvel Cinematic Universe movies include Ant-Man and the Wasp on July 6th, Captain Marvel opens on March 8, 2019, the sequel to Spider-Man: Homecoming on July 5, 2019, and Guardians of the Galaxy Vol. 3 in 2020.

]H/T Sunday Express]