Under the Dome is Stephen King's everything--including the kitchen sink--novel. It's got horror. It's got sci-fi. It's got corrupt small-town politics--the kind with the smiling-in-your face backstabbers King does so well. It's got well-realized kid characters, flawed good guys, beautiful on the inside heroines, and not one but two important dog characters. It's also got the expected amounts of blood, bile, urine, shit, and vomit, and enough dead bodies lying in pools of one or more of these substances to make even the strongest stomach quail at least a little.
In short, Under the Dome is Stephen King doing what Stephen King does best, namely, positing a what if situation and running like hell with it. He draws on all of our most basic fears (fear of the dark, of enclosed spaces, of abandonment, of death, of being different, of outsiders), throws in a double handful of paranoia, adds a dash of conspiracy theory, salts liberally with alcohol, marijuana, and meth, and stirs violently.
So, what if an invisible, indestructible dome were suddenly to drop down around a typical small town in America? As the novel opens we meet a doomed housewife having her first--and only--flying lesson. Yup, she and her flight instructor crash spectacularly into the dome. We are momentarily inside the consciousness of a woodchuck contentedly plodding along the road, just before--and just after--he is bisected by the dome dropping down. And we meet Dale Barbara--Barbie to all who know him (and yes, there are more than a couple "Where's Ken?" jokes)--as he is unceremoniously stopped by the dome as he's leaving town after suffering a beating at the hands of a group of young toughs. Barbie is the hero of the novel, the Stu Redman, to make the inevitable comparison to The Stand. The comparison is a valid one. But where The Stand is apocalypse writ large--millions dead, cities crumbling, good and evil vying for the very soul of humanity, Under the Dome is apocalypse under glass, more like a science experiment, or even more accurately like a badly maintained Habitrail.
There is so much juicy, sexy, gross, touching, and obscene stuff to discover in this giant, thousand plus page behemoth of a novel that attempting to synopsize wouldn't do anybody any good. Suffice to say it's one of King's best. His genius for picking at the psychological scabs of the human race until they bleed, and then letting them crust up and doing it all over again has been given full rein, and it gallops from page one to page one thousand seventy two.