Damon Lindelof is only interested in doing one season of Watchmen, at least for now

TV Guide

In a Deadline interview, Lindelof said Watchmen Season 1 won't end with a cliffhanger because it's limited to the books. When asked how many seasons Watchmen will run, Lindelof responded: "I’m not being flippant when I say that the answer is one. Does that mean that there isn’t going to be anymore Watchmen? Not necessarily. Does that mean that I will be working on subsequent seasons of Watchmen? I don’t know is the answer to that question. We designed these nine episodes to be as self-contained as the original 12 issues. We wanted to feel like there was a sense of completeness, to resolve the essential mystery at hand. Obviously, there is a potential promise for the further exploration of the world but like the seasons of Leftovers that I did as opposed to Lost, which was designed to have cliffhanger finales and a promise of future storytelling."