Of course, she really doesn't know Sy or the dedication he puts into making her photos look just right. Then again, she also doesn't realize how much this lonely man has taken a liking to her family through the photos he's developed year in and year out since Jake was just an infant. In fact, he views theirs as a picture perfect family and often fantasizes about being part of it.

With increased contact with the family in the store, Sy starts to take things a bit too far, and his behavior eventually begins to concern store manger Bill Owens (GARY COLE). When that eventually leads to some serious repercussions and Sy then discovers that the Yorkins aren't as perfect as he imagined, things begin to spiral out of control, eventually resulting in the involvement of local police detective James Van Der Zee (ERIQ LA SALLE).

Although that's obviously a necessity to see what one has shot, and people do enjoy sharing their photos with friends and family, the thought that a stranger could be perusing them and observing their family life, vacations and the like might be unnerving to some.

Imagine then, if someone in a photo lab became so accustomed to looking through a family's photos year after year that they eventually became obsessed with them and thought of themselves as part of the family. That's the premise of first-time writer/director Mark Romanek's "One Hour Photo," a generally well-made psychological thriller starring, of all unlikely people, Robin Williams as the obsessed clerk.

The antithesis of the sort of comedy many readers might now be imagining, the film starts at the end and then rewinds back to the beginning to tell its tale. Accordingly, the picture won't surprise many viewers by the way in which the basic plot unfolds. After all, we already know some of the ending, and the film also follows the general path of other crazed domestic figures getting into families' lives such as Glenn Close's Alex in "Fatal Attraction" and Rebecca De Mornay's Peyton in "The Hand That Rocks the Cradle."

Yet, while one pretty much knows in what direction the film is heading (or will develop to keep with the photography vernacular), the exact route and final image are in doubt until they occur. Romanek does a decent job keeping the viewer engaged and wondering how things will play out as well as curious and/or dreading what the obsessed man eventually does to end up in police custody.

Such films are only as good as the performer playing the villain and/or their delusional, antisocial or psychotic hang-up. In such regards, Williams is quite good and delivers a chilling performance into which he pretty much disappears (thanks, in part, to a decidedly different look for the thespian).

Playing against expected type, the actor appears to be continuing his recent trend of embodying dark and edgy characters - in films such as "Death to the Smoochy" and "Insomnia" - in purposeful or just coincidental response to the more schmaltzy ones in previous efforts including "Patch Adams" and "Bicentennial Man."

Williams also thankfully subdues his often manic energy (like he did in "Insomnia" but not in "Smoochy") and channels it into the character and his increasingly volatile obsession. Romanek effectively creates opportunities and complications for the character that serve as varying forms of stimuli and the actor more than credibly reacts to them.

The writer also gives Williams some terrific bits of occasional voice over narration about photography, life and the human condition in general, all of which come off as increasingly compelling and/or profound, particularly in contrast to the character's deterioration.

Playing the victimized family is Connie Nielsen ("Gladiator," "Mission to Mars"), Michael Vartan ("The Next Best Thing," "Never Been Kissed") and Dylan Smith ("Al's Lads") who all do fine jobs playing their respective parts of mother, daughter and son without coming off as clichés. Even so, only Nielsen manages to hold her own against Williams and not be overshadowed by his dead-on performance.

Meanwhile, Gary Cole ("Office Space," the "Brady Bunch" films) plays the store manager who must deal with the obsessed photo clerk and Eriq La Salle ("Color of Night," TV's "ER") briefly shows up as a cop trying to catch and stop the disturbed man before he does anything drastic.

That latter part is really one of two complaints I have regarding the film. Although not a total Hollywood copout, I felt that the "action" near the end was put in to appease viewers who are used to and thus expecting the villain to get his comeuppance at the end as often occurs in such thrillers. Thankfully, things don't conclude in such a contrived manner, and the ending and revelation of the man's motives does have a bit of a kick to it.

My biggest complaint, however, is that Romanek seemingly missed a golden opportunity in delivering a creepy blow to the viewer (either at the end or at some other big revelation point). During the film, we see that Sy has pasted hundreds of photos of the family on the wall from the floor to ceiling.

I kept imaging that they'd be used in a fashion similar to artwork's pointillism where they don't look like anything but randomly assembled photos up close, but come together to form some sort of overall image when viewed from afar. Since those photos are seen in various scenes, I figured that was going to be a big payoff somewhere in the film, but alas it does not occur.

Nevertheless, this is still quite an impressive debut from Romanek who previously helmed various music videos and the like. With his direction mostly coming off as restrained as Williams' performance - and that's meant in a good way - the film might not be the creepiest stalker film you'll ever see, and there are some slow moments. Yet, it's good enough that this is one picture you won't be able to get out of your mind. "One Hour Photo" rates as a 7.5 out of 10.