With decades of source material and legions of fans, it's no surprise that most films based on comic books are met with a tremendous amount of anticipation prior to their release. After all, until the boom in superhero cinema hit in the early 2000s, most – aside from Batman and Superman – had yet to make their big-screen debuts, placing even greater pressure on the few films that had had the chance to influence the future of the genre. Still, few superhero films fell as flat as these releases, which stand as some of the biggest letdowns to ever hit theaters.
Batman and Robin (1997)
Even with the campy tone adopted by the initial Batman film series, with director Joel Schumacher's Batman Forever, the prospect of its sequel bringing popular villains Mr. Freeze and Poison Ivy to theaters likely gave hardcore Bat-fans reason to hope that this chapter might redeem its predecessor. Alas, Batman and Robin marked an even steeper decline for the series, stripping the films of nearly any trace of their former glory. Without the involvement of Tim Burton (the director stayed on to produce Batman Forever), the film fell flat in terms of spectacle and narrative logic. It was such a misfire, in fact, that Warner Bros. pulled the plug on the in-development sequel and shelved the Batman franchise for nearly a decade before Christopher Nolan brought it roaring back to life with Batman Begins.