Studios cannot subsist on Marvel movies alone, 21st Century Fox co-COO James Murdoch told investors Monday at the JPMorgan Global Technology, Media and Telecom Conference.

“We don’t want to be a place where people say, ‘If it’s not a comic book movie, or something else, then I wouldn’t even take it to them,'” Murdoch said.

Instead, he argued that the company needed to attract new and original voices if it wants to “create whole new franchises.”

Not that Fox is eschewing the costumed heroes game entirely. The film division continues to license, reboot and spin sequels to the “X-Men” and the “Fantastic Four” franchises, two of Marvel’s crown jewels. It will keep doing so as long as they’re profitable or else it risks letting the rights fall back with Marvel’s parent company Disney.

“We think that’s a really rich part of that universe to sort of mine,” said Murdoch.

The Fox executive’s comments come as some industry observers are raising the possibility that the onslaught of films from Marvel and DC Comics runs the risk of eventually overwhelming and exhausting moviegoers. So far there’s no sign of defection, with “Avengers: Age of Ultron” crossing the $1 billion mark last Friday, but the true test will come next year when the number of superhero films will begin to increase dramatically.

Fox had one of its best years in 2014, releasing films such as “Gone Girl,” “The Fault in Our Stars,” and “Dawn of the Planet of the Apes,” that represented a wide range of budgets, genres and source materials. The strength of the slate was that it didn’t cater to one audience, Murdoch argued.

“We don’t want to be a film business that’s only making one type of picture, we want to be a film business that has a real diversity of output,” he said.

Fox’s broadcast business has suffered in recent years as shows like “American Idol” and “Glee” have struggled in the ratings. But Murdoch suggested the company had turned a corner thanks to the success of the music business soap opera “Empire” and the comicbook show “Gotham.” That shift will be reflected in the ad sales that emerge from its upfronts presentation and announcements, he predicted.

“To see some really big, broad accessible network shows like ‘Empire’ break out is really encouraging for the business in general,” said Murdoch. “We hope that the network has bottomed out and we’re now building on this new momentum.”