This season’s most challenging new show begins tonight.

“Flash Forward,” airing at 8 p.m. on ABC, has a complicated concept, which will immediately turn off viewers with short attention spans. Everyone in the world blacks out for two minutes and 17 seconds. During that time, most, but not all, get a vision of what they’ll be doing six months into the future.

FBI agent Mark Benford (Joseph Fiennes), his partner Demetri Noh (John Cho) and colleague Janis Hawke (Christine Woods) are assigned to try to figure out what happened by their boss, Stanford Wedeck (Courtney B. Vance).

They set up a global Web site, the Mosaic Collective, so that people can record what they saw in their visions, in the hopes of finding out who’s behind the blackout.

“Flash Forward” poses several questions: If people like their potential future, what can they do to make it come true? If they don’t, can they prevent it from happening, and how will that affect other people? What does it mean if a person didn’t have a vision?

The executive producers of the show are all sci-fi genre veterans: David Goyer (“Batman Begins,” “The Dark Knight”), Brennon Braga (“Star Trek,” “24”), Marc Guggenheim (“Eli Stone”) and Jessika Borsiczky (“Revelations”), so they know how to handle complex material in a way that viewers will appreciate.

“Flash Forward” is showing up at just the right time for fans of “Lost,” as that series enters its last season. It’s fast-paced entertainment for viewers who don’t mind thinking during their evening’s entertainment.