Insomnia, a story of morality that is less complex than it first appears to be, presents an agonizing dilemma. What would you do if you accidentally killed someone and knew you could get away with it? Would you do it? Could you sleep if you did? Such a quandary faces Will Dormer (Al Pacino), a reputable Los Angeles detective flown in to help solve a teenage girl's murder in Nightmute, Alaska. He greets the local police and takes over the investigation with an I've-seen-everything attitude and an admirable grasp of the scenario.

Dormer’s instincts usually lead him to circumvent proper legal procedure in order to pursue his quarry, and this has gotten him into deep trouble with the Internal Affairs Department back home. In love with his job, he is frustrated that I.A. seems intent on derailing his career. After Dormer makes his fateful mistake, however, he realizes that his career -- and, quite likely, his life -- would be over if he were discovered. He knows he has the ability to cover it up and so he does, but he runs into several complications, not the least of which involves loss of sleep, brought on by the combination of guilt and the never-setting sun of the Alaskan summer.

Soon, another character's involvement makes the consequences of Dormer’s actions more grave, turning his remaining investigation in to a nightmare. His suffering continues for the length of the movie, and director Christopher Nolan (Memento) competently invites the audience to suffer along with him. Subliminal flashes abound in this film -- they are the illusory visions we see when we haven't rested enough -- and, near the end, looking at Dormer's face is enough to make us all feel bleary-eyed as well.

However, by its finish, the movie squanders an opportunity to make its mark as either a morality play with a strong lesson or a deeper examination of morals and guilt that would leave its audience thinking about it afterwards. It ends with a cop-out. Dormer's decisions don't directly lead to his fate, and he is allowed a convenient way to escape.

This is too bad because, for much of its running time, Insomnia (a re-make of a 1997 Norwegian film of the same name) has what it takes to be a movie of impact, with strong performances and great photography. Pacino can play no-nonsense, ill-tempered, world-weary-yet-cocky characters with little to no effort, but here he gets to take this act one step further by infusing himself with racking guilt. There are moments where his character must give orders with his usual flair, yet he is still able to convey his self-doubt with his body language and his uneasy facial expressions.

Robin Williams impressively holds his own against Pacino in their scenes together -- perhaps only Williams, who once held staring contests with Matt Damon's Will Hunting, could be so sure of himself in such an unassuming manner that he could even unnerve Pacino. Nolan's cinematographer from Memento, Wally Pfister, gives the sunlit landscapes of Alaska a cool, awesome, yet lonely look, emphasizing the increasing isolation that Pacino's character feels.

Nolan uses the tools available to him to paint an effective portrait of guilt. As such, Insomnia is involving. Still, I thought it could have been more -- possibly a compelling study of how an individual’s morality drives the decisions that person makes. Instead, although on the right path, the film settles for an ending typical of other movies in the cat-and-mouse crime genre. It misses a chance at greatness, but that's nothing to lose sleep over. (Complete review posted on www.windowtothemovies.com.)

(Released by Warner Bros./Alcon Entertainment and rated "R" for language, some violence and brief nudity.)