A former Marine who did a tour of duty in Vietnam, Bickle is a socially inept 26-year-old taxi driver in New York City in the 1970s. He is increasingly disgusted by the seedy New Yorkers he encounters working the graveyard shift, and soon enough, he's paranoid, losing touch with reality, and acting out his vigilante fantasies: "Are you talking to me?" Robert DeNiro plays Bickle, one of the most iconic movie characters of all time.

A recently divorced, unemployed defense contractor, William Foster becomes increasingly disturbed throughout Falling Down. The film tracks him as he tries to make it across Los Angeles to get to his daughter's birthday party, even though his ex-wife has a restraining order against him. From his decision to abandon his sweltering Chevette in the middle of highway traffic to his altercations with a Korean grocer, the staff at a Whammy Burger fast food joint, and a group of gang members, among others, to his final standoff with an LAPD sergeant, Foster, played perfectly by Michael Douglas, grows progressively more violent and unpredictable.

The first of two women on this Top 13, Alex Forrest is as erratic and terrifying as anyone on this list. After a weekend affair with married New York attorney Daniel Gallagher, Forrest, herself a successful editor, becomes obsessed and begins stalking him. As Gallagher continues to ignore her, Forrest becomes completely deranged, pouring acid on his car and killing his daughter's pet rabbit. Her psychosis takes a turn for the worse when she kidnaps Gallagher's daughter, setting into a motion a series of increasingly violent incidents. Glenn Close received an Academy Award nomination for her portrayal of the spurned lover.

Perhaps no one on this Top 13 is as violently unhinged as Patrick Bateman, a fact that is made all the more amazing by the inability of anyone other than his victims to see the obvious signs of his derangement. A dashing and seemingly successful New York investment banker by day, Bateman - wonderfully played by Christian Bale - simply cannot control his bloodlust. He murders prostitutes, the homeless, and even colleagues with theatrical zeal. And when he works himself into such a tizzy that he admits everything to his lawyer, his bizarre confession is dismissed as a joke.

Two actors have played the role of Max Cady with fantastic results - Robert Mitchum in 1962 and then Robert DeNiro in the exceptional 1991 remake. Cady, among the most sadistic characters in film history, is fresh out of prison and out for revenge against his defense attorney, Sam Bowden, who he thinks suppressed evidence that could have exonerated him. Cady is out of his mind, first beating and raping one of Bowden's colleagues and then setting after the attorney's family and everyone else close to him in an uncontrollable murderous rage.

A drug-addicted, Beethoven-loving dirty cop, Norman Stansfield gleefully slaughters the entire family of a man caught skimming cocaine from him. When the man's daughter - who was picking up groceries during the murders - seeks revenge with the help of a mobbed-up hitman for the killing of her younger brother, Stansfield's patience thins and frequent pill-popping increases. Gary Oldman is typically fantastic as the agitated, explosive villain in French director Luc Besson's film, which also is known as Léon.

While a number of characters in Martin Scorsese's classic crime film demonstrate serious propensities for violence, only one, Tommy DeVito, does so in such an unpredictable and unnecessary manner. He shoots Spider - a busboy at a mob card game - merely for being slow with his drink order and later kills the teen for talking back, and he brutally beats a fellow gangster named Billy Batts to death for jokingly disrespecting him. Though Goodfellas was nominated for six Academy Awards, its only win went to Joe Pesci for his fantastic portrayal of the psychotic DeVito.

Writer Jack Torrance wasn't outwardly unhinged prior to accepting the winter caretaker job at an isolated hotel, where he'd be alone with his wife and son and have time to work on his book. But as the winter progresses, Torrance's mental state begins to unravel. He hears voices and sees people who aren't there - and then he completely loses touch with reality. Ultimately, he chases his family around the hotel with an axe. His rage culminates in the iconic bathroom scene with his wife in which Jack Nicholson as Torrance growls "here's Johnny" as he breaks down the door.

In the role that reinvigorated Dennis Hopper's career, he portrayed the psychotic Frank Booth, a foul-mouthed character that fits particularly well in a David Lynch film. Booth is clearly out of control; the only question is whether or not his instability is caused by the massive amount of gas he inhales throughout the film. In between huffs, Booth is both unpredictable and violent, and his attacks on the nightclub singer Dorothy are at times difficult to watch.

Screen legend Marlon Brando is Special Forces Colonel Walter E. Kurtz in Francis Ford Coppola's wrenching Vietnam drama Apocalypse Now. The army believes that Kurtz has gone rogue in a remote section of the Cambodian jungle and sends a team to kill him. When team leader Captain Benjamin Willard finds Kurtz, the army's fears are confirmed. Kurtz has Willard tied up and delivers a bizarre, twitchy lecture in which he recalls the horrors he has witnessed and praises the violent tactics of the Viet Cong. He later drops the severed head of one of Willard's soldiers on the captain's lap.

In this film loosely based on a book by Joan Crawford's own daughter about their relationship, the fading starlet gets her wish when she adopts a baby girl. But her behavior grows increasingly erratic as her daughter begins to grow up and doesn't quite follow Crawford's oppressive rules. Crawford rages against her for the most minor infractions: "No wire hangers, ever!" She chops the little girl's hair off and later attempts to kill her. Though Faye Dunaway played Crawford with remarkable intensity, she received a Razzie Award for her performance.

Though this character appears in a pretty much universally panned film and is played by Mark Wahlberg in one of is his earliest movie roles, David McCall is nonetheless as obsessed and uncontrollable as any on this list. McCall falls for Nicole Walker (played by Reese Witherspoon), whose father doesn't approve of their budding relationship. McCall becomes completely unpredictable when Nicole tries to end things, killing one of her friends, raping another, and absolutely terrorizing her entire family.

The second character portrayed by Christian Bale to appear on this Top 13, Jim Luther Davis is an ex-Army Ranger having a difficult time readjusting to life out of the uniform in South Central Los Angeles. Suffering from extreme post-traumatic stress disorder, Davis struggles to land a job in law enforcement, and his inability to control his temper gets him involved in several seriously dangerous situations. When he visits his girlfriend Marta in Mexico, he completely snaps upon learning that she is pregnant with his child in a scene that is brutally difficult to watch.