"The Rite" is loosely based on a book by Matt Baglio and, as the opening titles tell us, "inspired by true events." One can kind of buy into this claim for maybe the first forty-five minutes or so, at which time the film takes a sharp turn into hokey nonsense. There won't be a need for anyone who has seen the film in its entirety to fact-check the real story afterwards; its ridiculous and overblown last act speaks for itself. Indeed, what begins as a noble effort to speak eloquently about faith, religion and the darker powers that may or may not exist between this world and the next takes a sudden, disheartening nosedive midway through that stinks of the hands of a filmmaker whose vision was compromised in order to please studio heads only interested in cashing in with a rip-off of 1973's immortal classic "The Exorcist." When a character remarks, "What did you expect? Spinning heads? Pea soup?," it comes off as a self-referential wink to audiences. Pity that, by the end, "The Rite" has all but tossed spinning heads and pea soup into the brazenly stupid mix.

Michael Kovak (Colon O'Donoghue) has grown up around dead people, living with his widowed father Istvan (Rutger Hauer) in Kovak & Sons Funeral Home. Itching to escape, he laments to friend Eddie (Chris Marquette) that his only career choices as far as his dad sees it are to either be a mortician or a priest. Four years later, Michael is on the verge of finally taking his vows into priesthood, but plagued by an absence of faith he can't kick. He wants to resign, but mentor Father Matthew (Toby Jones) insists that, before he make such a monumental decision, he travel to the Vatican in Rome for a two-month program designed to reteach exorcism rites to the clergy. Shadowing Father Lucas Trevant (Anthony Hopkins), Matthew comes face to face with his first alleged possession victim: a young pregnant woman named Rosaria (Marta Gastini). At first he's not so sure she's not just a mentally ill woman—"She doesn't need a priest, she needs a shrink," he says—but pretty soon he'll have no reason to ever doubt the otherworldly forces of good and evil again.

"The Rite" was directed by Mikael Håfström, previously responsible for 2007's genuinely creepy haunted hotel chiller "1408" and now at the helm of a feature that wouldn't even rattle a mouse's foundation. The granddaddy of the possession genre is, and will probably always be, "The Exorcist," but more recent examples, like 2000's underrated "Lost Souls," 2005's astounding "The Exorcism of Emily Rose" and 2010's documentary-style "The Last Exorcism," have also ably pulled their own weight. "The Rite" appears to be following suit at the onset, the deliberate pace, thoughtful tone, and character-centric storytelling fascinatingly drawing the viewer into Michael's life and inner struggles. The screenplay by Michael Petroni (2010's "The Chronicles of Narnia: The Voyage of the Dawn Treader") stays with Michael in this first half, never wavering from his point-of-view, and the experiences he has with the sick Rosaria are left deliciously ambiguous as he, and the viewer, are left unsure as to whether she is really possessed or just faking it.

With the quickness of a light switch turned off, the film abandons all of the care and subtlety brought to the setup when Rosaria's condition is revealed to be inarguably supernatural in nature. From there, things only get more and more absurd and nonsensical—think the woebegone last act of 2004's theatrical version of "Exorcist: The Beginning," only worse—as red-eyed horses, toad infestations, diabolical disembodied voices, and numerous flat-footed jump-scare tactics take over. The final straw, though, is a climactic exorcism sequence so daffy and open to unintended audience mockery that it most closely resembles 1990's Leslie Nielsen/Linda Blair spoof "Repossessed." When the possessed person, decked out in a combination of blue-veined face make-up and CGI, taunts Michael by calling him "kissy lips"—and that said person happens to be Anthony Hopkins—it's difficult to take anything else that occurs very seriously. Adding insult to injury are characters who are suddenly shed of IQ points so they can make dumb decisions and an impudent pro-faith message that grows so preachy the movie begins to feel like an excuse for Christian indoctrination. There is a way to cinematically portray the reclaiming of one's faith that doesn't insult the viewer's intelligence—one example that comes to mind is Mel Gibson's character in 2002's "Signs"—but "The Rite" opts to just build a sermon into the finale.

As Father Lucas, Anthony Hopkins (2010's "The Wolfman") receives top billing, but plays second fiddle to newcomer Colin O'Donoghue, making his auspicious feature film debut. Hopkins is reliably fine early on, a laid-back authority figure who acts as tour guide to Michael's eventual awakening, then proceeds to chew the scenery with the voracity of a woodchuck whose lost his mind. Like the film, his performance plummets the longer it plays out. As Michael Kovak, O'Donoghue has to carry the bulk of the goings-on; his strong, sympathetic performance is the one constant even when everything around him has jumped the shark. In supporting roles, Alice Braga (2010's "Predators") is very good as Angeline, a journalist doing research on a story about the Vatican's exorcism course, while Toby Jones (2010's "Creation") and Ciaran Hinds (2010's "The Eclipse"), as priests Matthew and Xavier, do what they can with not much. Finally, Chris Marquette (2010's "Life During Wartime") makes an impression at the start as Michael's confidante Eddie, then vanishes after two scenes—a waste of a promising character and a talented actor.

For all of the hope that it misleadingly stirs up and all of the hogwash it ultimately becomes, "The Rite" is a sizable disappointment, a film that somewhere on its journey from written page to finished product has been stripped of its initially cerebral leanings for a dopey, excessively conventional lighting and effects horror show. There isn't a legitimately scary moment to be found. Meanwhile, the evocatively chilly, always handsome cinematography by Ben Davis (2010's "Kick-Ass") gives off the impression that the picture is as dignified as it easily could have been before director Mikael Håfström, whether by his own doing or those of the powers that be, botched the results. What does the loud, swirling chaos of the finale buy the picture? Nothing but trouble. There is a better film lurking within "The Rite," an ambition that bubbles to the surface early on before sinking to its deepest depths. That, alas, is where it stays.