In “Batman v Superman: Dawn of Justice,” the Dark Knight and the Man of Steel duke it out and the audience loses. Ever since director Zack Snyder first announced the movie at the 2013 San Diego Comic- Con, the frenzy of anticipation has reached “Star Wars” proportions. Here, finally, was the film that would unite the two most iconic superhero characters in all of comic-book history and pit them against each other. The hook is irresistible, even if you can’t tell your DC from your Marvel. The premise of two unbeatable titans clashing has a deep, almost primal pull: Homer knew this when he made Hector and Achilles fight in The Iliad.

And comic-book writers have known this since 1940, when the Human Torch took on the Sub-Mariner in Marvel Mystery Comics #8 (fire versus water; the fight of the century!) Superheroes have been brawling with each other for decades— sometimes because of a misunderstanding, other times because of moral or philosophical differences. The upcoming “Captain America: Civil War,” which will force most of the characters from the Marvel Comics movie universe to pick a side between Iron Man or Captain America, is based on a storyline from the books that explored the tricky balance between freedom and security and what sort of limits and regulations we are willing to accept in order to feel safe and protected.

“Batman v Superman: Dawn of Justice,” written by Chris Terrio and David S. Goyer, is about a billionaire vigilante who picks a fight with a super-powered alien for accidentally toppling one of his skyscrapers. The movie borrows heavily from Frank Miller’s seminal 1986 “The Dark Knight” mini-series, which told of an aged, bitter Batman who was forced out of retirement by a surge in crime and had to defend his brutal methods against a government-lackey Superman.

But Snyder and his screenwriters have dumbed down Miller’s smarter, more resonant narrative and turned it into an apology for the apocalyptic finale of “Man of Steel,” in which Superman (Henry Cavill) and the evil General Zod (Michael Shannon) flattened half of Metropolis during their climactic showdown. Although the buildings that were demolished in the previous film were all curiously empty — Snyder took care not to show any fallout or casualties from the fight — the level of CGI-overkill was so great that it was insulting to insist Superman’s victory didn’t come with an enormous body count, which would be a betrayal of the character’s essence.

So Snyder walks back that defense at the start of the new picture, opening with billionaire Bruce Wayne (Ben Affleck) watching the Superman-Zod fight from ground level and seeing one of his buildings — now suddenly full of people — laid low. This radical revisionism, which treats the audience like idiots, is the first indication that “Batman v Superman: Dawn of Justice” exists primarily to live up to the second half of its title — to serve as a launching pad for a DC Comics film franchise to mirror the wildly profitable cinematic universe Marvel Studios has carefully developed since 2008’s “Iron Man.”

In other words, “Batman v Superman” is a sleek, stylish commercial by a studio desperate to birth a new cash cow post-Harry Potter. Almost every aspect of the film — from the shoehorning of Diana Prince (a beautifully blank Gal Gadot), aka Amazonian warrior Wonder Woman, into the plot to pointless cameos by several other fan-favorite DC characters — feels like it was decided in a boardroom instead of a writers’ pen. Moving away from the golden, airy feel of “Man of Steel,” Snyder apes the dark, brooding aura director Christopher Nolan brought to his “Dark Knight” trilogy. But he doesn’t have the breadth or vision to match the style.

Affleck, who gets top billing over Cavill in what is essentially a sequel to “Man of Steel,” fares OK as Bruce Wayne, but these characters are too played out, too familiar, for any actor to make much of an impression. Only Jesse Eisenberg, as the maniacally evil Lex Luthor, seems to be trying to do something different with his role: He lets you see the wires short-circuiting inside the villain’s head when he schemes. But the movie has no use for him other than as a plot device, a mechanism to set certain events in motion, with no apparent motivation.

This huge, unwieldy movie is busy and overcrowded: There’s a subplot involving terrorists, Amy Adams’ Lois Lane is in constant need of rescuing and Holly Hunter plays a gullible U.S. senator. Unlike “Man of Steel,” which couldn’t avoid the draggy pacing of origin stories, “Batman v Superman” is loaded with incident and moves briskly. But the only things that register are fleeting, inconsequential beats, such as a dream sequence in which Batman imagines he’s in a future realm in which Superman and his fellow evil aliens have conquered the world. That scene, which is shot in one long take, is weird and exciting and strange, a brief glimpse at the bolder, more original movie Snyder is capable of making.

But after the financial failure of “Watchmen,” his epic, R-rated adaptation of the Alan Moore graphic novel that failed to rake in the expected cash, Snyder learned his lesson. He’s no longer going to take any big risks. “Batman v Superman: Dawn of Justice” does a good job of building up your anticipation for the title bout, and the fight, when it finally arrives, delivers big time. But if you’ve seen the trailer, which has been inescapable, you already know most of the story’s surprises, including the third-act arrival of another infamous villain. That character should have been kept as secret as the movie’s ending, which is one of the few things in “Batman v Superman: Dawn of Justice” you haven’t seen before and leaves the story, if not dangling, then at least begging to be continued. Don’t worry: Filming on “The Justice League Part One” is scheduled to begin in April.