'Sup, /co/. Have some spoilers.
Steve Rogers is Nomad now and leads the Secret Avengers, formed by Black Widow and Falcon. Scarlet Witch, Hawkeye and Ant-Man went their different ways, and Ant-Man isn't even in the movie.
Steve's team all have minor roles. Early on, they rescue Scarlet Witch and Vision from the Children of Thanos and send them to Wakanda so Black Panther and his sister Shuri can extract the Mind Stone from the Vision and guard it against Thanos. When Thanos' forces invade Wakanda in the end, they return to help. Steve is the one that manages to kill Thanos' main enforcer Corvus Glaive after he kills Vision and defeats everyone else that tries to stop him. It is also in this scene that he uses the shield for the first time since the ending of "Civil War".
Thanos attacks the Asgardians' ship in search of the Space Stone, which Loki trades for Thanos' pardon and the lives of the refugees, becoming Thanos' advisor. Thor is severely beaten and cast out into space by Thanos, where he is later found by the Guardians of the Galaxy, who had been following Thanos' trail of destruction across the galaxy.
Star-Lord, Gamora, Drax and Mantis go to Knowhere to consult with the Collector, but find him being tortured by Thanos for the Reality Stone. Meanwhile, Thor, Rocket and Teen Groot visit the Dwarf King Eitri (Peter Dinklage), who forged Mjolnir, for weapons. Eitri has also forged the Infinity Gauntlet, and Thanos has cut off his hands so he can not build something powerful enough to destroy it. Thor finds an axe, Jarnbjorn, made from the same metal as Mjolnir, but it is unfinished, so Teen Groot gives his wood to make the handle.
There's a gag that, although Eitri is considered a "dwarf", he's actually massive by mortal standards. Thor goes up on his knee.
Thor doesn't get his eye back. He wears the eyepatch for the entire movie.
