(CNN) "It Chapter Two" is in many ways a victim of its own success, a sequel virtually assured a vast audience that proceeds to undermine its virtues by conspicuously overplaying them and overstaying its welcome.

Horror movies are usually known for their economy, but "It" drags on nearly three hours, until a level of numbing repetition creeps into its elaborately staged scares. The result is a movie with a lot of strong moments, but which feels too much like "It: Endgame" or "Once Upon a Time ... in Derry," aspiring to epic qualities that it doesn't earn or possess.

The first movie , which focused on a group of barely pubescent children forced to deal with an ancient evil embodied by the killer clown Pennywise (Bill Skarsgard), had a real charm in the bonding of those self-proclaimed losers, which brought Stephen King's novel -- previously turned into a mostly admirable miniseries -- to life.

As in King's book, this chapter reunites those kids 27 years later to finish what they started. It has the benefit of seeing the youths juxtaposed with their adult incarnations -- played by James McAvoy, Jessica Chastain and Bill Hader, among others -- but spends so much time building toward the inevitable climax that it's only a marginal improvement over the weak ending of the TV version.

Indeed, McAvoy's Bill -- a writer whose stammer returns as old fears are revisited -- is teased about his inability to deliver good endings, a joke that strikes a little too close to home. (There's also a King cameo in which he takes the author to task, just in case anybody wasn't clear on the meta nature of the gag.)

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