Reign Over Me is, among other things, a bracing demonstration that you can never judge a film by its premise. Adam Sandler... in a classic-rock fueled drama... from the creator of the series The Mind of the Married Man... playing a cloistered, traumatized widower who lost his wife and children in a 9/11 plane crash — it sounds like the perfect storm of bad ideas. But as it happens, Reign Over Me is a thoughtful, involving and sometimes moving film that almost (and I do mean almost) justifies its use of 9/11 as a dramatic device.

Things don't start off that well, as the opening credits kick off with a montage of a tousle-haired Sandler tooling all over Manhattan to the simpering strains of Graham Nash's "Simple Man." His Charlie Fineman is a former dentist who's managed to carve out a comfort zone within his shell-shock after losing his wife and three daughters. With the help of an at-first-shady-seeming business manager and protective landlord, he rules over a sparsely furnished apartment where he masters video games, "jams" in a music room, and obsessively remodels his kitchen. For the most part, he's reverted to a responsibility-free adolescence.

His old college roommate, Alan Johnson (Don Cheadle), who spots Charlie one day on the street and is initially befuddled by Charlie's inability to remember his former life, is the prototypical responsible husband and dad. But this successful dentist is peculiarly stifled, silently bristling over an existence that has robbed him of his autonomy and unable to communicate his frustrations to anyone around him. Every now and then he fishes for advice from the sympathetic but hardly amateur shrink (Liv Tyler) who also works in his office building. When Johnson is propositioned by an unbalanced and very attractive patient (Saffron Burrows), he's appalled enough to do the right thing and dismiss her; but he's also intrigued enough that we see just what kind of danger zone he's in.

Instead of straying conventionally, Johnson joins Fineman in what he describes to his wife (Jada Pinkett-Smith) as "Charlieworld." In this world, you get Chinese food whenever; hang out late at rock and roll clubs; sit through Mel Brooks marathons at will, and so on. When his wife calls him on his absences, Johnson protests that he's trying to help out a troubled friend (and indeed Charlie is troubled, occasionally launching into paranoid harangues against Alan; he's also so thoroughly shut down that he can't muster an empathetic word when Alan learns his father's just died), but she's got Alan's number. "You envy his freedom," she tells him in one pained late-night talk.

But Alan has, during this time, been coaxing Charlie out of his shell, and the story takes several drastic turns from that point. It's to director Mike Binder's credit that at each of these turns the heretofore delicately unfolding tale could very easily turn into maudlin, smarmy nonsense but then... does not. Binder's humanism is such that he even manages to concern himself with the pain of Johnson's initially predatory temptress, whose involvement in the rest of the scenario is implausible but strangely touching in the end.

The performances here are largely first rate, with Cheadle not surprisingly leading in subtlety. Tyler is as appealing as she's ever been, and Pinkett-Smith is a strong, sympathetic presence in what could have been a stock role. As for Sandler, well, he's the one you see working at it. He marries the halting cadences and shuffling mien of his old stand-up work with sudden outbursts of frenetic emotion that recall Dustin Hoffman in Rain Man. It is a very visible performance, but he makes it signify, and if your tear ducts get a workout in the climactic scene where he finally stands face to face with his estranged in-laws, well, you'll know the man is doing his job.