Cedar Rapids Opens Friday at the Michigan Theater, Quality 16 and Rave

From the outset, “Cedar Rapids” appeared to be custom-made for me.

I’m a fan of stars Ed Helms and John C. Reilly; the movie’s a comedy set in the Midwest (and was filmed in Ann Arbor); and I’ve enjoyed director Miguel Arteta’s work previously, particularly “The Good Girl.”

So why did “Cedar Rapids” end up feeling blandly forgettable, despite its moments of sweetness and humor?

For one thing, Phil Johnston's screenplay never veers far from its tried-and-true, fish-out-of-water storytelling formula. Helms plays Tim Lippe, a sheltered insurance salesman who has spent his entire life within the boundaries a small Wisconsin town. When a celebrated work colleague dies suddenly, Tim is sent to represent his insurance agency at an annual convention held in the “big city” of Cedar Rapids, Iowa.

Once there, he befriends a similarly-inclined straight arrow, Wilkes (occasional scene-stealer Isiah Whitlock Jr.), who’s the first black man Tim’s ever talked to; the convention’s loud, boorish, self-appointed party animal, Deanzie (Reilly); and Joan (Anne Heche), a bored mom who seeks temporary escape from her conventional life each year at the convention.

But in order to uphold his agency’s winning streak at the convention — which Tim’s boss (played by Stephen Root) is pressuring him to do — Tim will have to eschew the ethics that make him who he is.

Helms is absolutely the right man for “Cedar Rapids,” because he winningly makes Tim’s earnestness and naivete endearing rather than eye-rollingly tiresome. And the chemistry between the friends has appeal. But generally, the characters are cartoonish, one-dimensional “types” more than fully realized, flesh-and-blood individuals.

Arteta offers occasional moments that promise more complexity. Blustering, over-compensating Deanzie — words that could also describe Reilly’s performance — is captured secretly sneaking a peek at a picture of his ex-wife, whom he claims to despise; and as Tim watches Joan talk to her family on the phone, the reality of who she really is in her day-to-day life settles on them both.

But then you have Alia Shawkat, playing a good-hearted hooker (is there any other kind?) who’s charmed by Tim’s obliviousness; Root, the pushy, self-absorbed boss; Sigourney Weaver, as Tim’s former seventh grade teacher who, taking on the now-compulsory “cougar” role, sleeps with Tim for kicks; and Kurtwood Smith, the holier-than-thou, hypocritical convention leader (Orin Helgesson) who preaches religion while also angling for bribes.

There’s a problem with this last plot point, in that you wonder about no other attendee, over the years, trying this ploy on Orin, leaving Tim to face his ethical quandary in complete isolation. And some of the film’s funniest moments are deflated by virtue of having already appeared in the film’s trailer.

But it’s nearly impossible to resist Helms, particularly in scenes where Tim is sublimely wowed by travel clichés (rental cars, holidomes, hotel rooms, and complimentary peanuts on a flight), or when he explains to Joan why he sincerely believes that his work as an insurance agent is important, though it sounds boring to most people.

So “Rapids” has its charms, and its off-and-on laughs — but it’s not quite as funny as it aims to be.