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Agents of SHIELD: What the Hell is Up With Coulson's Doppelgänger?

Agents of S.H.I.E.L.D.'s Phil Coulson is dead, but that hasn't stopped him before. According his partner Agent Melinda May, she was with him until the very end, but the Season 6 trailer teases another story for Coulson actor Clark Gregg. Coulson -- or someone who looks very much like him -- returns for the very brief cameo at the end of the trailer, but he doesn't appear to remember the events of the series so far. When someone asks him if he's from S.H.I.E.L.D., he simply responds, "Never heard of it."

Of course, Coulson is no stranger to death. He already died once in 2012's The Avengers, when Loki shoved his scepter through his heart. However, Nick Fury -- Coulson's director and longtime friend -- wasn't ready to let him go just yet. Using Kree biology and a secret experiment, his scientists brought Coulson back to life. This procedure would ultimately be undone by Ghost Rider in the Season 4 finale, leading to his death in Season 5.

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However, it looks like this Agents of S.H.I.E.L.D. death is going to stick this time. According to Gregg, he will play "this other very mysterious person, who is not Phil Coulson," in Season 6. Here are just a few ways -- both old and new -- that the show could explain away this Coulson doppelganger.

Time Travel

Considering it was a major plot device in Season 5, time travel naturally tops the list. Last year, Coulson's team was thrust into the future by a Kree monolith. There, they discovered Earth had been destroyed, and they were told there was nothing they could do to stop it. Nevertheless, Coulson and his team traveled back to present day and successfully prevented Graviton from ending the world. By the finale, Coulson -- dying from an earlier injury -- bid his team a tearful goodbye and walked off into the sunset with May.

RELATED: Agents of SHIELD's First Season 6 Trailer Is a Massive Spoiler

As harrowing and tragic as the events of Season 5 were, the time loop had one major benefit. Though Fitz died in action in the season finale, an earlier version of him still exists. That is to say, he was not sent to the future with his teammates through the Kree monolith. With a little help from an alien anthropologist called Enoch, Fitz entered cryosleep earlier in the season and eventually "caught up" to the rest of the team. He returned to the present with the team, meaning that two versions of him existed simultaneously: the one who experienced the future and the one still in cryosleep. As glimpsed in the Season 6 trailer, the team will make good on their promise to rescue Fitz from cryosleep, which means he'll be back despite his death.

Of course, only one version of Coulson existed in this particular time loop -- that we know of, anyway. However, the team seriously meddled with the timeline, which could cause heretofore unseen consequences. For example, they may have created an alternate timeline, a storytelling device that has frequently cropped up in the comics. Perhaps the fallout rippled backwards, creating a version of Coulson that never joined S.H.I.E.L.D. and became unmoored from time. This probably isn't the most likely scenario, but it is worth mentioning since it was such a major piece of Season 5 and, possibly, Avengers: Endgame.

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