LOS ANGELES — Shortly after she took over DC Comics six years ago, Diane Nelson noticed a glaring problem at the company owned by film and TV studio Warner Bros.

DC’s vast library boasted some of the most popular female superheroes and super villains in the industry dating back to the 1940s — including Amazon princess Wonder Woman, Kryptonian heroine Supergirl and Batman nemesis Poison Ivy. But comic book characters had been targeted almost exclusively at boys and men.

“We realized there’s this untapped opportunity,” said Nelson, whose large office door is covered in an image of Wonder Woman. “There’s clearly demand in the marketplace to serve the young girl market.”

Now Nelson, 48, is trying to zero in on that audience with the launch of a new superhero franchise aimed at girls 6 to 12.

The Los Angeles-area company’s DC Super Hero Girls — a youthful, feminine twist on popular characters — is hitting store shelves for the first time this year with a trove of new action figures, dolls, costumes and other products. The ambitious rollout starts in March with a limited release in Target stores and followed by a global launch in July. The initiative reimagines popular heroes like Wonder Woman and Batgirl — plus more obscure characters such as Bumblebee and Katana — as high-schoolers.

And it’s not just toys. Warner Bros., also based near LA, hopes the franchise will also generate revenue across its film and television businesses.

The push comes at an important juncture for the studio. Warner Bros. Chief Executive Kevin Tsujihara has bet big on its stable of DC superheroes to drive box-office sales and television ratings. The studio is hoping upcoming movies like “Batman v Superman: Dawn of Justice,” “Suicide Squad” and “Justice League Part 1” can help reverse its box-office fortunes after suffering several flops last year. DC has seen success with Christopher Nolan’s “Dark Knight” films, but the unit has lagged behind Disney’s Marvel Studios, which dominates the superhero market.

Nelson, who also runs Warner Bros.’s consumer products business, has overseen major licensing brands such as Harry Potter and The Hobbit. She says young girls have been mostly excluded from the superhero action. American consumers spent $7.4 billion on girls’ toys last year for kids aged six to 12, according to research firm NPD Group, and a third of those sales were dolls.

“I think this is one of the most important things that DC will do,” said Geoff Johns, DC’s chief creative officer. “It’s changing the culture of what superheroes are.”

The studio has already unveiled a series of short online videos and will soon premiere a 44-minute animated TV special on Turner Broadcasting’s Boomerang network. Boomerang will also air the girls’ video shorts and music videos. Warner Bros. and Turner are both owned by Time Warner Inc.

The TV special and animated shorts, which will be promoted by Cartoon Network, play off the personalities and abilities of the young heroes, who are still learning their powers and place in the world. Wonder Woman is an overachiever but still a vulnerable teenager. Supergirl can fly, but she’s socially awkward. Harley Quinn is mischievous, though not yet the murderous villain she later becomes in the comics.

The Super Hero Girls program spans a wide range of products, including Batgirl and Supergirl costumes, a Wonder Woman shield that fires plastic projectiles, and books. DC plans to release a smartphone and tablet app in March, which will include videos, games and character bios.

If successful, Warner Bros., may develop a movie based on the characters, said Nelson, a veteran Warner Bros. executive who played a key role in shepherding the Harry Potter franchise.