Why these heroes may not save the day for Warner Bros.

The Batman v. Superman trailer leaked.
Source: Warner Bros.

In 1978, Warner Bros. convinced the world a man could fly in "Superman." A decade later, Tim Burton brought Batman to life in an otherworldly Gotham City and sparked a successful franchise.

Now, the movie giant is banking on both Batman and Superman to save the day. After its debut last week at San Diego Comic-Con, the new trailer for "Batman vs. Superman: Dawn of Justice" won massive Internet buzz and lots of kudos from comic die-hards. But is it too little, too late?

In recent years, the superheroes of DC Comics have struggled to capture the imagination of moviegoers, with the notable exception of Christopher Nolan's "Dark Knight" trilogy.

The unit's struggles have come in the face of a super-powered blitz by rival Marvel, which has all but conquered the box office with top-earning franchises like "The Avengers," "Iron Man" and "Guardians of the Galaxy".

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At least for now, Warner is basking in the afterglow of the latest "Batman vs. Superman" teaser. Whether that can translate into narrowing the gap with Marvel and resonating with audiences in a way that translates into box office money, however, remains an open question.

"When I was a kid, Superman and Batman were every bit as big as Spider-Man. Nobody had heard of Iron Man, and "Guardians of the Galaxy" was Geeksville," said Barton Crockett, media analyst at FBR Capital Markets, said. "Now the Marvel stuff is everywhere."

Numbers don't lie

Industry watchers have scratched their heads as DC/Warner have significantly underperformed Marvel Studios, Crockett said.

To wit: Warner all but abandoned its Green Lantern franchise after a 2011 film based on the space-faring hero just barely cracked $200 million worldwide in 2011. (Productions and marketing costs reportedly neared $300 million.) Still, a reboot is planned for 2020.

The studio's mostly forgotten "Jonah Hex" science fiction Western pulled in just over $5 million in its first weekend, earning it a spot on Box Office Mojo's 50 worst debuts for a 2,500-plus-theater opening. Even "Man of Steel," featuring DC's flagship hero, earned less globally than five Marvel Studios films, and just barely edged out two others.

Yet for competitor Marvel, the tale of the tape has been entirely different. The top 10 Marvel Studios movies since 2005—excluding Sony's Spider-Man and Fox's X-Men franchises—netted $8.3 billion. By comparison, DC pulled in $4.6 billion.

Marvel Studios, however, was mostly absent from San Diego Comic-Con this year. That left the floor to Warner and 20th Century Fox, which promoted its X-Men properties and Fantastic Four reboot.

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Yet it was Warner that clearly stole the show, whetting fans' appetites with previews of "Dawn of Justice" and "Suicide Squad." The studio also unveiled concept art for films further down the line, including "The Flash" and "Green Lantern Corps."

Read the tweet here.

Read the tweet here.

"Dawn of Justice" certainly upped the ante for Warner, said Jeff Bock, senior box office analyst at Exhibitor Relations. At least for now, it appears to be a foregone conclusion the film will deliver, he added.

"No matter how good or bad you think the film is, it was always going to open with $150 million or more," he told CNBC. "Nothing's going to stop that when you put these two comic legends on the screen together."

How audiences respond to Ben Affleck as Bruce Wayne, aka Batman, is the biggest X-factor for Warner, Bock said. The character is pivotal to DC's shared universe and its "Justice League" film, Warner's answer to the Avengers. If fans reject Affleck, the studio may have to put another actor under the cowl, he said.

Not just for 'comic nerds' anymore

A big year of change at Comic-Con

Warner will not only face casting scrutiny but heightened competition in the superhero genre. The battle for consumer dollars is intensifying, with ticket sales in decline and growth in foreign markets moderating, according to Cowen and Co.

Cowen analyst Doug Creutz said in a recent note that there's still an appetite for comic book adaptations and noted that their quality is on the upswing.

However, the number of superhero releases per year will double in 2016, and history shows—most recently in the animated segment—that saturation leads to smaller box office hauls across the board.

Reliance on superhero films reflects a broader trend in which studios invest primarily in expensive franchises, he wrote. Creutz sees the lack of diversity increasing risk throughout the industry because big-budget sequels make for costly mistakes. In a crowded field, some are sure to fall short of expectations.

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While Warner has traditionally had one of the more diverse release schedules, it is coalescing around marquee franchises such as DC Comics, Lego and Harry Potter franchises next year, said Creutz.

"We think Warner's track record over the last 15 or so years with franchise films has generally been best-in-class, but we also think that the gluts in the superhero and animation genres make their DC and Lego bets relatively high risk," he wrote.

Crockett said it's unfair to lump all comic book adaptations together under the umbrella of superhero movies. Still, he warned it was imperative that Warner finds its niche this time around.

"It's very, very big business. It's very important for these companies," Crockett said. "It's not just a plaything for our comic book nerds anymore."