You don’t have to know anything about the popular comic-book superhero going into Green Lantern, but it might help clear up some things in this cluttered movie, the sort of big, empty summer blowout they warn you about. Ryan Reynolds plays Hal Jordan, a hotshot test pilot who reluctantly becomes part of an intergalactic corps of peacekeepers after he inherits a glowing green ring that turns him into the titular hero. The movie can be harmless fun when whenever Hal suits up. Unfortunately, most of Green Lantern is bogged down with Hal’s boring backstory, his relationship with an ex-turned-boss (Blake Lively), and a subplot involving a scientist (Peter Sarsgaard) who comes in contact with an alien. It doesn’t help that Reynolds plays Hal like an extreme-asshole version of Tony Stark. The other Green Lanterns are kinda cool. So is the big blob of a baddie they take on. Everything else crashes hard.