But the conceit isn’t realized fully enough to ensure the affirmative response Warner Bros. would doubtless like to hear. As is, it’s more in the realm of a definite “maybe.”
Carrey is introduced as Carl Allen, a sad-sack bank-loan officer who still hasn’t recovered emotionally from his divorce three years before. Although his pals Peter (Bradley Cooper) and Rooney (Danny Masterson) try to nudge him out of his shell, Carl’s answer to virtually every overture that involves anything but staying home and renting DVDs is an evasive “no.”

A chance encounter with an old acquaintance inspires him to attend a self-help seminar, where a steely-eyed guru (Terence Stamp) preaches the power of saying “yes” to every opportunity — forging a covenant with the shell-shocked Carl to adhere to this simple code.

To his surprise, the “just say yes” strategy yields welcome results — and equally significant, failing to do so invites disaster. Carl’s grudging agreement to assist a homeless guy, for example, inadvertently brings about his introduction to Allison (Zooey Deschanel), a free spirit to whom he’s instantly drawn (in a faint echo of “Eternal Sunshine of the Spotless Mind”) — and thanks to his newfound attitude, with whom he’s very much in tune.

Similarly, unquestioningly approving bank loans to eccentric characters — the timing of which could probably be better, given the present mortgage meltdown — benefits Carl in unexpected ways, if not quite triggering the logical “pay it forward” scenario that would help lend ballast to this slender premise.

Instead, director Peyton Reed (“The Break-Up”) — working from an adaptation of Danny Wallace’s book by Nicholas Stoller, Jarrad Paul and Andrew Mogel — lets the movie lapse into an uneven, episodic mode. That format yields the occasional juicy bits (Carl thwarting a suicide attempt; an interlude with his aged neighbor, played by Fionnula Flanagan), but not enough of them to sustain the level of manic energy Carrey can unleash at his best. Almost too conveniently, the propositions thrown Carl’s way also generally avoid anything that’s so uncomfortable as to risk brushing up against the limitations of a PG-13 rating.

In terms of concocting laughs, Carrey receives minimal help other than from Rhys Darby (HBO’s “Flight of the Conchords”) as his nerdy boss, who has a fondness for idiotic nicknames and throws movie-themed parties seemingly catering to fringes of the Comic-Con crowd. (Those scenes amusingly if somewhat conspicuously showcase Warner Bros. properties, including the “Harry Potter” franchise — also from “Yes Man” producer David Heyman — and “300.”)

From a technical standpoint, the movie makes unusually good use of Los Angeles landmarks as a backdrop for Carl and Allison’s budding romance, from the Hollywood Bowl to the Griffith Observatory. Mark Oliver Everett of the band Eels collaborated on the score and contributes several songs.

Mercifully, “Yes Man” finally arrives at a place that lets a bit of air out of the pervasive self-help bubble. It’s only too bad that the movie isn’t slightly more adept at helping itself.