Lefevre ("Twilight") has the role of Julia, small-town reporter who has only recently moved to the town of Chester Mills before it gets a case of the evil domes. The adaptation, by "Y The Last Man" creator Brian K. Vaughan is a modification of the character who is a lifelong resident of Chester Mills and a long-time antagonist of the piece's villain, city councilman and used car dealer Big Jim Rennie. That meaty and insane role goes to "Breaking Bad's" Dean Norris, who I'm sure will just kill in the bunker scene if that makes its way into the show.
CBS is billing this as a series and not a mini, which, again, has obviously required some modification from the source material which saw Chester Mills and its residents trapped for something like three weeks. As a concept, it's a cool one, but the novel is one of King's worst (in the afterword to the book, King talks about unearthing the manuscript--which he began over 30 years earlier--and dragging it into the present day). Still, maybe a dramatic overhaul can smooth over some of the roughest, almost "Tommyknocker"*-level edges while not completely losing its mind when it comes to the story's resolution.
*That very bad book has the distinction of being the worst adaptation of King's work, featuring Tracy Lords and a tube of laser lipstick and the residents of a small town slowly descending into camp.