Last week, Stranger Things confirmed that filming and production for season 4 have resumed following coronavirus delays.

Now, new theories that emerged that one villainous character may not be dead after all and could return in the new season.

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Stranger Things fans have been patiently waiting for season 4 since the start of 2020. The series' writers confirmed the new season would be arriving this year. In the wake of the pandemic, however, things quickly changed.

Netflix shut down all productions for its shows in March, a move that obviously impacted Stranger Things 4David Harbour who plays Hopper revealed in a March interview that season 4 is likely to premiere in 2021 due to the unforeseen delays.

Stranger Things

Now, new theories have emerged that could mean a character from season 1 is making a return. For those that need a recap, Dr. Brenner was the research lab director who forced Millie Bobby Brown’s Eleven to participate in mind power experiments that spied on the Russians.

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Dr. Brenner appeared to be killed by the Demogorgon in season 1. However, in season 2, an orderly hinted to Eleven that he might still be alive. Most recently, in season 3, Stranger Things shows an eery glimpse of an unnamed American locked in a Russian jail cell. Some fans believe that the person may actually be Dr. Brenner.

As we saw with the first teaser of season 4, Hopper is alive after being presumed dead at the end of the last season. However, he is captured and forced to work at a Russian camp. Given that Stranger Things 4 will involve the Russians again, it's possible that Dr. Brenner could resurface.

Matthew Modine, who played Dr. Brenner, is very open to reprising his role for Stranger Things 4. He tells NME that he loves reading fan theories about the villainous character.

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“I love that the fans are trying to figure out where Dr. Brenner is, because we’re all wondering, you know, is he in the Upside Down? Did the Demogorgon drag him away? Is he going to re-emerge?”

He teases that Dr. Brenner's story may not be over yet, further fueling the fan theory he will return next season.

“And the show’s creators, the Duffer Brothers, have said that unless you see a body, the character’s not dead," he says. "And obviously we never saw Dr. Brenner’s body.”

Modine also shares why he thinks Dr. Brenner isn't as bad as fans make him out to be.

“What did he do that’s so bad? “I’ve watched the show, and I don’t think Dr. Brenner ever killed anybody," he says. "[Whereas] Millie Bobby Brown – Eleven – killed two interns in the hospital and killed the people in the hamburger shop. Then she flipped a van – and you’d imagine this probably killed the people who were in that van.”

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The Duffer Brothers revealed some key secrets about what’s in store for the Hawkins gang and Hopper back in May.

“Although it’s not all good news for our ‘American’; he [Hopper] is imprisoned far from home in the snowy wasteland of Kamchatka, where he will face dangers both human… and other.”

“Meanwhile, back in the states, a new horror is beginning to surface, something long-buried, something that connects everything. Season 4 is shaping up to be the biggest and most frightening season yet. And we cannot wait for everyone to see more. In the meantime, pray for the American.”

Millie Bobby BrownFinn WolfhardGaten MatarazzoCaleb McLaughlin and Noah Schnapp are returning for the new season. Sadie SinkJoe KeeryWinona RyderNatalia Dyer and Charlie Heaton are also reprising their characters. Stranger Things newcomer Maya Hawke will also appear as her character Robin along with fan-favorite Priah Ferguson who plays Erica.

Since its delay, the release date for Stranger Things 4 has not been revealed. In the meantime, the teaser featuring Hopper is available to watch below.

Do you think Dr. Brenner will return in Stranger Things 4? Let us know your thoughts in the comments below.