Written and directed by Ricky Gervais and Matthew Robinson, "The Invention of Lying" has an encompassing, consummately original premise, the kind that creates a whole new world and then finds the dryly comic and absurdist humor within its tweaks on reality. Also a love story, as well as a decidedly pointed dissertation on the validity and purpose of religion, the film perhaps bites off more than it can comfortably chew, but isn't without a pleasing portion of food for thought for viewers tired of being unchallenged by mainstream studio fare.

Set on an alternate earth where lying does not exist—the very word is absent from the dictionary because there is no concept of what it is—Mark Bellison (Ricky Gervais) is a hapless screenwriter working in the research department at Lecture Films, a successful motion picture studio (the movies, like all of cinema, consist of people sitting in chairs reading to the camera about moments in history). When Mark is fired for his inability to make the Black Plague interesting, he finds himself without the money to pay his rent. And then, while at the bank, a synapse in his brain sparks and he chooses to embellish how much money he has left in his account. It saves him from being evicted, yes, but, having stumbled upon the very idea of lying, Mark finds that this power can be used in any situation, whether it be to better himself or get his way, brighten up someone else's day, or bring comfort to those that need it most. It is out of this latter use of fibbing that he devises the notion of a God and an afterlife, at first simply to put his sick elderly mother (Fionnula Flanagan) at ease about her fears of dying, and then to bring that same level of comfort to the world at large.

"The Invention of Lying" has a better beginning and middle than ultimate wrap-up, with its droll initial introduction to an existence where the sometimes harsh truth is all people know and have ever known transitioning to Mark's legendary discovery of lying and the steps he takes to make the world a little happier and more peaceful. Broad sight gags are a hoot—the local nursing home is labeled on the outside of the building "A Sad Place for Hopeless Old People," and the low-rent motel on the edge of town is called "A Place for Intercourse with a Near Stranger"—and so is the straightforward dialogue as characters are constantly speaking their mind. The use of faith as a plot point is courageous from writer-directors Ricky Gervais and Matthew Robinson, particularly since the notions of a God and Heaven are depicted as nothing but a figment of Mark's imagination that the rest of the population naturally buys into. Gervais, an atheist in real life, may receive some flack, but doesn't deserve to; he is respectfully careful not to pinpoint any one specific religion and is simply reimagining what a planet totally free of mistruths might be like for the people in it.

Less successful is the romance between Mark and office worker Anna McDoogles (Jennifer Garner), whose blind date goes wrong from the start when she informs him she's not attracted to him and will probably finish masturbating upstairs before they leave for dinner. Anna is out of his league, but, as they spend more time together, they become good friends. Still, she can't let their relationship go further because she wants a father to her future children to have solid genetics. Since Anna's belief that looks are everything—at least at the onset—comes not from telling the truth or lying, but from her own shallow hang-up, it puts a black cloud over her head. The viewer wonders what Mark sees in her and why she grows to mean so much to him. The outcome of this subplot is more low-key than most romances, but it also appears to be holding back. That, ultimately, is the whole film's downfall, the premise in general lacking a catharsis where others start figuring out what lying means. Because this never happens, the long-winded third act loses steam as it runs around in circles and doesn't really go anywhere.

Ricky Gervais (2009's "Night at the Museum: Battle of the Smithsonian") has an everyman quality that, combined with his sardonic humor and vulnerability, makes him immediately identifiable and a pleasure to watch. He's also a mighty fine actor; a scene where he says good-bye to his ailing mom on her death bed and gives her a final moment of reassurance right before she passes on will have many audience members rightfully wiping their eyes. Gervais sells his characters without ever falling into over-the-top histrionics, and his naturalism helps to keep the material from getting too cute or sudsy. As Anna, Jennifer Garner (2009's "Ghosts of Girlfriends Past") is comedically skilled herself, but her role is not developed much beyond the surface. Jonah Hill (2009's "Funny People"), as a suicidal neighbor who finds a reason to live, and Louis C.K. (2008's "Role Models"), as a not-all-there bar dweller, respectably fill out the parts of Mark's confidantes. Tina Fey (2008's "Baby Mama") is underused but makes the most of her one-liners as Mark's assistant, Shelley, who tells him she has loathed every minute working for him.

"The Invention of Lying" provokes after-viewing thought and discussion—always a plus—and is adept at balancing the funny stuff with a sobering levity. An uneven last half-hour that ends things with more of a whimper than a bang notwithstanding, the film is ambitious and stands apart from, or defies, clichéd situations. Is the world better or worse without lying in it? Neither, directors Ricky Gervais and Matthew Robinson surmise, only different and no less flawed. If a little fabrication or a tiny falsehood can save a person's life, or even add a smile to somebody's day, then what harm is there in that? Outward honesty, it turns out, is not always the best policy, nor is it the same as being honest with one's own feelings and emotions. It's a fine line, shaded in colors that transcend the black and white, if not every problem, of Hollywood moviemaking.