By "stand-alone," NBC means "little to no Hayden Panettiere," as the 13-episode season of Reborn will feature a brand-new cast. There are, however, still possibilities for cameos by the original characters, NBC Entertainment president Jennifer Salke said in a statement.
Despite the sudden cancellation of the show in 2010, NBC couldn't ignore its popularity. "The enormous impact Heroes had on the television landscape when it first launched in 2006 was eye-opening,” said Salke. “Shows with that kind of resonance don’t come around often and we thought it was time for another installment."
Don't expect any spoilers, though. Reborn promises to be "shrouded in secrecy" until the air date. In the meantime, you'll have to content yourself with binge-watching the previous four seasons on Netflix. (Deadline)