Reese Witherspoon is extremely popular with the American movie-going public and it's not hard to understand why. She's blond for one thing; she's perky and pragmatic for another. She's attractive but not threateningly so. While her pink, puffy facade can conceal a nagging, even annoying woman, she has yet to reveal a dark undercurrent.

Mark Ruffalo, her costar in this ethereal romantic comedy is a contrasting, though no less American type -- the ruffled boy next door who can be awfully sweet when he chooses, but who usually emits a recalcitrant, Hush-Puppy vibe. His laconic persona is possibly depressive and certainly capable of crossing the boundaries of propriety. 

Pairing these two was not an obvious casting decision. It pays huge dividends by neutralizing the high saccharine content in the fairytale about a doctor, Elizabeth, and a widower, David, who meet somewhere between life and death in a fabulous San Francisco apartment. The actors counteract their own baggage and those of their characters. Ruffalo gives Just Like Heaven that so-called indie edge, softening Witherspoon, and Miss Populism allows him to flower under the mainstream lights. 

Elizabeth is a workaholic trauma doctor -- amiable, multi-tasking, and competent beyond belief.  Hardly a push-over, she's devoted to her career and patients and therefore has no life outside the ER. Ruffalo fits snugly into the role of David, a pea coat-wearing landscape architect helplessly moping about two years after his wife's death.

After Elizabeth gets into a car accident, David sublets her coveted apartment with mahogany wainscoting and terrific rooftop views. She then starts appearing to him and only him (he learns he can conjure the fastidious physician by putting a cup of coffee on the table, sans coaster).  Figuring out where things are headed after their first few encounters isn't difficult, but revealing too much of the plot would detract.

The gist is that Elizabeth transforms David from a sodden, grieving couch potato into Prince Charming. And David, while turning Elizabeth into Lizzie, becomes her advocate and savior. The sparks are refreshingly platonic, partly due to the story's constraints and mainly because neither actor is stereotypically sexy. They don't make the earthiest tandem to begin with. What passes for a sex scene, their chaste night spent together with hands touching, is quaintly satisfying.

The fact that Elizabeth exists in a ghostly nether-region would be a romantic non-starter outside the movies. Yet serious points about euthanasia (parallels with the Terry Schaivo are hard to shake off) jump out from this morsel of madcap populism. David avers that a coma is "way better than dead." And there's a spiritual bias against materialism and science summed up in his observation, "Machines don't know everything." The light manner in which the subject matter is handled undermines anyone using it to make political points however.

Surprisingly, the source material is not homegrown schmaltz but a novel titled "If Only It Were True" by young French writer Marc Levy. The life-and-death premise could easily turn trite in the hands of different filmmakers. The casting of the principals, fine supporting work by Jon Heder, Donal Logue, and Dina Waters, plus crisp execution prevent it from being corny in a debilitating way. The brain activity never dips too low and the funny, charming picture never takes itself too seriously.

The experience of watching Just Like Heaven is captured by the last line --"Righteous" -- uttered by Darryl, the laid back clerk in an occult bookstore whom David consults. This sentiment might gain legitimacy in the eyes of younger moviegoers because it's delivered by the hilarious Heder, star of last summer's phenomenon Napoleon Dynamite. 

(Released by DreamWorks and rated "PG-13" for sexual content.)