Warner Bros.

This may sound unfathomable to younger moviegoers, but 20 years ago today, the superhero film died a seemingly irreversible death. Batman & Robin was supposed to be one of the biggest tentpoles of the summer: It was the continuation of an enormously successful Warner Bros. franchise that had begun in 1989 with Batman, which starred one of the most expensive movie stars alive (Arnold Schwarzenegger, paid a handsome $25 million for his trouble). A follow-up, Batman Unchained, was already in development. A spinoff focused on sidekick Robin (Chris O’Donnell) was on the books. Then the movie came out.

Many an appreciation of Joel Schumacher’s second Batman film, starring George Clooney, Uma Thurman, 100 metric tons of neon lighting, and 2,000 fog machines, has been written over the years. For the movie’s 20th anniversary, The Hollywood Reporter has assembled a terrific oral history of its tortured production, including some typically self-effacing quotes from Schumacher (who has never been afraid to acknowledge what went right and wrong with the film). But Batman & Robin’s biggest impact was changing how Hollywood approached superhero movies as a whole—it proved such films couldn’t be assembled with the ease of any other Hollywood action picture, and that the genre was not as “critic-proof” as once thought.

The warning signs were already there with Batman Forever, Schumacher’s first go-round with the Caped Crusader, which starred a new actor (Val Kilmer) and embraced a broader, more kid-friendly storytelling approach than Tim Burton’s two attempts. That film made a perfectly healthy $184 million in 1995—but that was far less than Batman, which had grossed $250 million six years earlier. Reviews were far less kind, and on-set relationships was somewhat troubled, with Tommy Lee Jones (Two-Face) telling Jim Carrey (The Riddler), “I cannot sanction your buffoonery,” and Schumacher calling Kilmer “childish and impossible.”

The phenomenal success of Batman had spawned a new wave of Hollywood superheroes: There were hits like the Teenage Mutant Ninja Turtles and The Crow, bombs like Judge Dredd and The Rocketeer, and cult favorites like Darkman and Tank Girl. The producer Jon Peters was trying to get a rebooted Superman film into theaters, with Nicolas Cage going as far as doing costume tests for a film tentatively titled Superman Lives. No studio had ever really considered the idea of a “linked universe” that would eventually become commonplace—the idea of Superman and Batman, brethren in the comics pages, interacting onscreen was not a priority.

Superhero movies were not very different from any other action event of the 1990s—they were star-driven exercises first and foremost, made with little fealty to their source material. No Batman film really resembles any of the hero’s best-known comic-book works (which Christopher Nolan would later draw from for his Dark Knight trilogy). Marvel Comics, which in the 1990s was in the midst of serious financial struggles, was a long way away from funding its own movies and steering their production to be more faithful to their works of origin (a highly successful project it began in 2008 with Iron Man).

Today, any studio would balk at the idea of paying a huge star like Schwarzenegger a massive paycheck (he made $38 million in today’s dollars to play the villainous Mr. Freeze). Superhero franchises are about more than one film, and getting less well-known stars (as Marvel did with actors like Chris Evans, Chris Hemsworth, Tom Hiddleston, and others) is a way to plan for the future economically, rather than get tied into giant paychecks right away. Batman & Robin did star a relatively cheap Batman—George Clooney, then best known for the TV hit ER—but its budget was far larger than most of its superhero rivals.

Batman & Robin debuted to horrible reviews and worse word-of-mouth, with particular derision aimed at Uma Thurman’s Mae West-esque take on Poison Ivy, Mr. Freeze’s repetitive insistence on ice-related puns, and the merchandise-focused action sequences. Schumacher had made a film that leaned even further into the campy 1960s tone of Adam West’s Batman at a time when audiences were craving something more serious. I saw the film in theaters, aged 11, and even though it was aimed straight at my demographic, I emerged confused—it was probably the first time I had truly disliked a movie.

Batman & Robin eventually grossed $107 million domestically, below its reported $125 million budget (the usual rule of thumb is that studios take half of a film’s gross). The big summer hits of 1997 were The Lost World: Jurassic Park, Air Force One, and Men in Black, though they were all eventually eclipsed by the Christmas release of Titanic. Schumacher’s plans for Batman Unchained, which would feature villains like The Scarecrow and Harley Quinn, were cancelled. He tried pitching the studio on a darker take, based on Frank Miller’s iconic comic Year One (which rebooted Batman’s origins), but the studio wasn’t interested in keeping him on board.

Batman & Robin is a joy to watch now for all its over-the-top glory; there are hundreds of little delights to pick up on, from Clooney’s obvious pain at every moment he’s onscreen, to Chris O’Donnell’s strangled exclamation of the line, “A batbomb?” But it’s also worth noting as a cautionary tale. The next significant attempt at a comic-book movie came in 2000 with X-Men, which was put in the hands of a real, up-and-coming artist (Bryan Singer, coming off The Usual Suspects) rather than a studio hack. It starred relative unknowns Hugh Jackman and James Marsden, and its supporting characters were not mega-budgeted stars, but well-regarded thesps like Patrick Stewart and Ian McKellen. Most importantly of all, it wasn’t made with solely kids in mind—and that more serious pitch worked to sell the film to a wider audience.

The same approach hit with Spider-Man in 2002 (directed by Sam Raimi), and although “serious” comic-book movies would encounter their own roadblocks (see Ang Lee’s Hulk, or the Ben Affleck-starring Daredevil), it’s proven a more than reliable template, turning the superhero flick from embarrassing sub-genre to Hollywood backbone. There’s no doubt the ridiculous excesses of Batman & Robin had to happen to force things in that direction. The real question is, could there soon be another massive box-office flop? As comic-book weariness abounds, and studios hurriedly set up as many franchises as possible, will the Justice League or the third Avengers movies miscalculate as grandly as Batman & Robin, forcing the industry into a dramatically different direction? Hollywood has always been a boom-and-bust business—and make no mistake, another bust is on its way.

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