Some people will complain about this romantic comedy, calling it fluffy, predictable, easygoing entertainment. But that doesn't necessarily make it a bad movie. Just Like Heaven will probably be welcomed with open arms by middle-aged and older audiences, who often can't see their way past all the action-packed violent films that open almost every weekend. And there might even be some crossover younger viewers -- maybe the girls who like to look at Mark Ruffalo.

He plays David, a landscape architect who's been leading a sad, solitary life in San Francisco since his wife died a couple of years earlier. Searching for a new apartment, he takes one that was recently and very mysteriously vacated.

But by that point, even though he doesn't know why this apartment is available, everyone watching already does. It was the home of Elizabeth (Reese Witherspoon), a young doctor who's trying to get ahead, and has forfeited any kind of normal life for her career. She's just finished a 26-hour shift when, while then heading off to a rare dinner date, she doesn't pay enough attention to the road and drives smack into a truck. (Please don't tell this to Albert Brooks, who had a fairly similar scene in Defending Your Life.)

Anyway, the apartment is available, and David moves in, mostly to sit around and drink beers and try to forget that he was once happy. Then, inexplicably, Elizabeth shows up and starts yelling at him to get out of her apartment. She doesn't know who she is or what she's doing -- or even that she's dead -- but she sure wants her apartment back. This leads to David thinking that he might be losing his mind, and to Ruffalo showing a flair for physical comedy.

That's about it: Boy meets ghost, ghost wants boy out of her life. But because this is a romantic comedy, boy and ghost form a team.

Along with some very funny episodes, both Ruffalo and Witherspoon get to play a wide variety of emotions, and there's that all-important chemistry. They make a good onscreen match, when they're bickering and when they, inevitably, grow closer.

Accolades also go to Jon Heder, seen by the art house crowd last year in the title role in Napoleon Dynamite, and here, with his hair unkinked, as Darryl, a guy who runs a supernatural bookshop. He successfully plays the character as a laid-back dude -- a very laid-back dude who really wants to believe in the occult.

Visual effects, the kind that have Elizabeth walking through walls and even disappearing into other people's bodies, are very good. But there's also a lot of clutter getting in the way of really enjoying the film. The ongoing problem in so many of today's big studio movies of sticking in pop songs just to sell soundtrack albums is out of control here. It's not that there are too many of them, but that they're used in a terribly unoriginal manner to complement the storyline. So "Just My Imagination" plays when David can't figure out if Elizabeth is real; "Brass in Pocket" -- a really bad cover of it -- is on when a statuesque and forward upstairs neighbor (Ivana Milicevic) puts some moves on David; and "I Put a Spell on You" (at least it's the Screamin' Jay Hawkins version) is heard when David is searching through that special bookshop.

Though most of this is light and funny, the script goes through a few major mood changes. Some of it is serious, some is a little weepy, some veers very close to being schlocky. The business of David refusing to talk about his late wife adds nothing but a touch of maudlin to the film; he could have just been a lonely guy who's unlucky in love. Yet when part of Elizabeth's memory comes rushing back, the scene in which it happens is nicely done.

It's too bad that the often-sparkling dialogue of Just Like Heaven is mixed in with errors in judgment -- such as the film's multiple endings. This is a romantic comedy, so of course they're happy. But there's a distracting few minutes that get between a good ending and one that's added on. The film easily could have ended just as happily with its last two segments taken out.

Just Like Heaven; Rated: PG-13; Directed by Mark Waters; Starring Reese Witherspoon, Mark Ruffalo, Jon Heder