When the Avengers get back together again following their split up in Captain America: Civil War, they’re faced with their most powerful adversary yet, Thanos. The foster father of Gamora and Nebula (of the Guardians of the Galaxy), Thanos wants to cull the herd, so to speak, by eliminating half the population of the universe to reduce the drain they’re putting on its natural resources. Like any dedicated environmentalist he’s just trying to help, but to execute his plan, so to speak, he must first collect all of the Infinity Stones, forged in the Big Bang. When gathered together they offer the bearer absolute power. Thanos can then achieve his goal with a snap of his fingers.

As the story begins, Thanos has destroyed the ship carrying the Asgardians away from their home planet, which was itself destroyed in Thor: Ragnarok (try to keep up with the plot points from at least some of the previous 153 Marvel comic book movies...