When Jon Favreau’s Iron Man hit theaters in May 2008, it wasn’t just a superhero movie; it was the shockwave that launched the Marvel Cinematic Universe (MCU). Today, accessing this pivotal film requires understanding its "index"—a term we use here to mean its availability across streaming services, physical media, digital retailers, and even its placement within the larger MCU chronology. Below is your definitive guide to finding and watching the film that started it all.