Avengers: Infinity War - 13 Major Plot Reveals From Trailer 2

6. Loki Is "Captured" By The Black Order

As already explored, we know that Thanos will meet Thor, Loki and (possibly Bruce Banner) when he boards the Asgardian refugee ship from the end of Thor: Ragnarok. Thor will "die", Banner will escape and SOME of the Asgardians will flee (presumably led by Valkyrie, Korg and Miek). But Loki won't get away that easily.

The trailer confirms that Loki ends up captured by the Black Order, with the background suggesting that there's an almighty battle on the ship that leaves it in ruins. Proxima Midnight's stance definitely suggests he's a prisoner rather than a willing participant.

From here, there are two schools of thought: either Loki is killed in vengeance for "failing" Thanos (even though the Mad Titan absent-mindedly gave him the Mind Stone in The Avengers), or he willingly hands over the Tesseract and aligns himself with Thanos. It would fit his self-preservation instincts after all, but it's still unclear which route the film will go down.

Either way, Thanos ends up with the Space Stone, which could be ominous for the God Of Mischief.