Few comedies have at stake the very fate of humankind, but "Dogma," by writer/director Kevin Smith, is not your usual comedy. It is an imaginative and surreal adult fable bursting with wild ideas, fantastical creations and boisterously funny characters.

In this self-dubbed "comic fantasia," Bartleby (Ben Affleck) and Loki (Matt Damon) are fallen angels who have spent all of recorded human history exiled in Wisconsin.

When the pair learn that a PR-hungry New Jersey church has resurrected the archaic Catholic practice of plenary indulgence (by which one is absolved of all sin by merely walking into the church), they see it as their opportunity to get back into heaven. However, by returning to paradise, they will be defeating God's will, thereby destroying the whole of creation, which is based upon an omniscient and infallible deity.

The unlikely mortal chosen to intercede on heaven's behalf is Christ's last living relative, an abortion clinic worker named Bethany (Linda Fiorentino). Metatron (Alan Rickman), God's go-between angel, appears to Bethany and dispatches her to New Jersey to foil the angels' plan. Along the way, she encounters friends and foes of varying degrees of divinity, all of whom have their own motivations for aiding or abating the "Last Scion," who is herself coping with a world where agnosticism is suddenly no longer an option.

The genius of Smith is that he takes some seriously dense subject matter and turns it into one of the funniest films of the year, without coming off as cheap or showy. The film is a comedy of ideas, certainly a comedy of passionate argument. And the key to it is Smith's treatment of religion as more familiar than sacred, something so much a part of his life he can joke about it and pick at it, zero in on its flaws and quirks and keep asking questions.

"Dogma" is at its best when it goes on the flights of Socratic fancy that have characterized Smith's previous films ("Clerks," "Mallrats" and "Chasing Amy"); perhaps no other filmmaker pens such entertaining, though often self-conscious, dialogues. Struggles with faith are conveyed through the energetic and often poignant exchanges between his hilarious characters.

Though Smith hasn't made great strides as a visual stylist, his scripting is better than ever. Not only does he present his usual rants on sex and pop culture (including an amusing treatise on John Hughes' 1980's teen flicks), but his approach to religion walks an amazingly slender tightrope: It's worldly without being cynical and irreverent without being disrespectful.

Unfortunately, the film's scale prevents it from achieving the intimate character depth of Smith's previous film "Chasing Amy." Nonetheless, the amazing cast gives the film its profundity. The chemistry between old pals Affleck and Damon is perfect and each portrays an angel with distinctly human qualities.

Damon, surprisingly, has a great gift for comedy (at one point he sings the theme from the late TV series "Martin") and Affleck convincingly runs the gamut from a thoughtful admirer of humans to a jealous, malicious deity.

Alan Rickman stands out as a weary and frustrated spokesman for God who still longs for the tequila he can no longer drink. Chris Rock imbues his role as Rufus, the forgotten black apostle, with the same energy and candor that has propelled him to stand-up stardom.

And the priceless Jason Lee steals every scene he's in as a demonic hellspawn who casts his lot with Loki and Bartleby. Fiorentino, however, struggles at first to convey a lapsed Catholic, but her performance eventually keeps the celestial film's center planted firmly in the human realm.

Smith fans especially will celebrate the return of the gloriously crude Jay (Jason Mewes) and Silent Bob (Smith, himself). The duo, who have been seen in all of Smith's previous films, become Bethany's earthly protectors. The two get some of the biggest laughs and, although they seem like unlikely prophets, their presence injects the film with an engaging comic book sensibility.

"Dogma" is clearly Kevin Smith's most ambitious film and, from the witty introductory on-screen notes, the audience is reminded that "Dogma" is, first and foremost, a comedy.

Of course, many Catholics, especially Church officials, will not be amused by what Smith calls a "parable" and a "trifle of a film." The lampooning of Catholic images and the diatribes against church doctrines (Jesus is said to have been black and God is represented as a woman) will surely offend some viewers. Yet, at the core of this indulgent exercise in spirituality is a deep faith in God, Jesus, salvation and basic goodness. Even when he stoops to toilet humor, Smith's eyes look toward heaven.

"Dogma" is one of the most pro-religious (and, specifically, pro-Catholic) films in recent memory. Though there are well-aimed jabs at the Church, it is clear that Smith embraces the Catholicism he's satirizing. In fact, it is so exclusively Catholic that some viewers may find themselves left out in the cold.

Kevin Smith is indeed a practicing Catholic and "Dogma" is his attempt to deal with his own questions of faith. It is less an attack on the Catholic Church than an open letter, albeit a comical one, to the American Catholic community, provoking discussion. Ultimately, "Dogma" is about the renewal of faith and, despite the packaging, that's a message everybody can use.

Four out of five shamrocks

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