3. Its Source Material Is Pretty Rubbish
The movie is based upon The Infinity Gauntlet, a six-part comic storyline from 1991. Here follows spoilers for that story, so if you want to stay pure, click to the next slide. Here's what The Infinity Gauntlet is about in a nutshell. It's the first part of a saga written entirely by Jim Starlin, made up of Infinity Gauntlet, Infinity War and Infinity Crusade and it focuses on the cosmic clashes of various godly beings who battle for control over all of time and space, and the realities therein. The macguffin in the final part of the saga is something called The Cosmic Egg. Sounds great. Thanos is a Titan, an eternal being born on Saturn's moon of the same name. Growing up with his brother Eros, he became obsessed with death, eventually falling in love with its physical embodiment, Mistress Death. To woo her (which you assume they're still going for what with the 'court death' gag at the end of the first Avengers movie) he pledges to wipe out half of the population of the universe, cos that will really get her going. To do this he acquires the Infinity Gauntlet, made up of Infinity Stones, which gives its wearer complete control over Time, Mind, Soul, Power, Reality and Space. The big six, basically. He wipes out half of the universe's population in the blink of an eye and the Avengers become alerted to this when people just start vanishing all around them. An all-powerful creature named Adam Warlock rounds up Earth's Mightiest Heroes and a bunch of godlike beings, like Galactus and Eternity (who is the spiritual embodiment of the entire universe) and prepare for battle. While this happens, Thanos spends the whole comic whinging that Death doesn't love him. The whole comic. "Why doesn't she love me? Why doesn't she love me, I've been so cool to her." He's the cosmic version of the Nice Guys of OkCupid. Everyone fights, Thanos wins. Then Thanos' daughter Nebula (Karen Gillan in Guardians of the Galaxy) surprises him and nicks the Gauntlet. Everyone, including Thanos, fights her instead, and trick her into reversing everything that Thanos has done. It's a mess, consisting of two big fights and countless shots of planets and gods exploding. How will they make this into not one but two films, when all the villain has to do is click his fingers and people disappear?