NBC's sci-fi series Heroes is being revived as a 13-episode limited series, with creator Tim Kring back at the helm but a new cast of characters and a self-contained storyline that's "shrouded in secrecy."

The series, which aired from 2006-2010, will return in 2015 as Heroes Reborn, NBC Entertainment president Jennifer Salke announced Saturday, adding that some former cast members might "pop" back in for cameos. The characters and plots will be introduced in a digital series that will precede the TV premiere.

Heroes was a big hit in its first season, averaging 14.5 million viewers, but ratings declined sharply afterward as some fans began to sour on its heavily serialized story about a group of people with superpowers.