Marvel's Agents of S.H.I.E.L.D. have returned in a new Season 6 trailer, and they've brought a Coulson-shaped mystery with them.

At 1 minute and 23 seconds in length, the trailer opens and closes with fan-favorite S.H.I.E.L.D. Director Phil Coulson. In the first scene, he is merely a hologram, a projection through which he imparts some director-to-director advice to Alphonso "Mack" Mackenzie. When he reappears at the end, though, he appears to be not only real, but alive.

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Coulson, of course, peacefully accepted his death at the end of the Season 5 finale. After a tearful goodbye to his team, he walked off into the sunset with Agent Melinda May to spend the rest of his days in rest and relaxation. As she tells Mack in the trailer, she "was there until the very end" with him.

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However, he resurfaces in a brief shot at the very end of the trailer -- and it seems he doesn't have any recollection of S.H.I.E.L.D. at all. In a voice over, which may admittedly be misleading, someone asks Coulson if he's from S.H.I.E.L.D., to which he responds, "Never heard of it."

The trailer also drops some other hints about what's to come in the upcoming sixth season. For example, it appears as though the S.H.I.E.L.D. team heads into deep space to rescue Fitz from his cryosleep and break the time loop established in Season 5. This paves the way for plenty of action and galactic horror, as established in one shot where a man's body is shredded by crystals. It also introduces a host of new characters, over which Mack provides some ominous narration: "We don't know where they're from. They're extremely powerful."

Agents of S.H.I.E.L.D. is set to return for its sixth season in July 2019 on ABC with 13 new episodes; the series stars Ming-Na Wen, Chloe Bennet, Henry Simmons, Iain De Caestecker, Natalia Cordova-Buckley and Elizabeth Henstridge.