The Plot:

   Earl Brooks (Costner) is a successful businessman, loving husband and caring father, but, of course, he has a dark secret. Brooks attends Alcoholics Anonymous meetings but he isn’t addicted to alcohol. Instead Brooks’ addiction is murder and he is teased and encouraged to indulge in his addiction by his schizophrenic alter ego, Marshal (Hurt). Marshall derides Earl about his hesitance to give in to Marshall murderous ambitions. 
  While Earl has managed to stay “clean” for a while, Marshall, who often seems more than just a figment nuisance, finally wins out and goads Earl to murder. But, a photographer calling himself Mr. Smith (Dane Cook) captures a chance photo of Earl’s face after witnessing him committing a double murder. As it turns out Earl is not just any murderer, he is a “famous” serial killer, the Thumbprint Killer that for years has managed to elude Detective Tracy Atwood (Demi Moore), who has made finding the Thumbprint Killer somewhat of a personal quest. 
To complicate things even more, Smith is not after money. Instead he wants Earl to apprentice him and show him how to commit grizzly crimes and get away with it. 

The Point:

Mr. Brooks is by far one of the most attention-grabbing movies I’ve seen so far this year. One thing I found quite compelling is the central dilemma focused though the lens of a storyteller; how do you make an audience sympathize with a serial killer? In Mr. Brooks we are acquainted quite quickly with the idea that the compulsion to murder is something that Earl does not enjoy. From the time he chooses his victims (the Thumbprint Killer always kills in pairs) to the last moments of their lives, Earl is deliberate, patient and methodical. But at the same time he abhors his actions, suffers from nightmares stemming from the murders and repeatedly asks posthumous forgiveness from his victims.
The performances by the actors were unforgettable. The interplay between Costner and Hurt as opposing forces of Earl’s personality proved quickly to be a good choice of casting. These days with technological marvels occurring around every corner Costner could have very easily played both roles (after all how many Jack Sparrows were there in At World’s End). The decision to cast a separate actor, in my book, was the best choice as each actor can give their all to represent their own influence over their characters.
The movie also embarks on some minor and relatively unobtrusive exploration into the notion that Brooks’ murderous compulsions may even be hereditary. It is good food for thought without burdening the story.
If there is any drawback to the movie it is the subplot involving Moore’s Detective Atwood. Being apprehended by the authorities is a reasonable fear, or at the very least a job hazard, for any criminal but Atwood never even gets close leaving a loose end that seemed to be very rushed and sloppy, not the ordinary work of the Thumbprint Killer.
  Obviously this movie contains adult themes and some disturbing content and thus I do not advise it for the weak hearted or the under aged.