Filmmakers often explore the dark side of the human psyche. Tales of murder, madness, and mutilation seem to keep audiences captivated. Many of these films rely on true stories about infamous serial killers to showcase these themes.

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The best fictionalized movies about real-life serial killers do not glamorize the slayers or disregard the victims' perspectives. Instead, they emphasize how authorities and survivors fight to bring harmful individuals to justice. These films also examine what motivates people to hurt each other. This list covers five of the best and five of the worst films about known serial killers.

Best: Zodiac (2007)

Zodiac

The Zodiac terrorized residents of northern California during the late '60s and early '70s. This serial slayer — who developed a reputation for taunting police and the media with letters — was never apprehended.

David Fincher's film focuses on both journalists and investigators trying to uncover the identity of the elusive killer. Moody and intense, Robert Downey Jr., and Mark Ruffalo. The film captures both the fear and the curiosity generated by the murders in stunning, at times graphic, detail.

Worst: From Hell (2001)

From Hell

Jack the Ripper, whose imprint on pop culture persists into the present, slaughtered London sex workers with surgical precision in 1888. The killer's identity was never uncovered, but theories abound about who he was.

The Hughes Brothers directed this adaption of Alan Moore's graphic novel of the same name. While the graphic novel is a brilliant, provocative retelling of the case, the film lacks the deeper philosophical contexts that make Moore's work so good. From Hell stars Johnny Depp and Heather Graham, both of whom seem out of place in gritty Victorian England.

Best: Monster (2004)

Monster

Aileen Wuornos is likely one of the most well-known female serial killers ever. Statistically, the vast majority of repeat murderers are men. A sex worker, Wuornos murdered seven male clients across Florida between 1989 and 1990. Monster digs into Wuornos' troubled past, full of abuse and neglect, in order to explain what pushed her to murder.

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Charlize Theron won an Oscar and endless acclaim for her portrayal of Wuornos, who was executed by the state of Florida in 1992. Monster provides no easy answers. Instead, it demonstrates how violence begets violence.

Worst: Gacy (2003)

Gacy

Gacy is a campy, unintelligent dark comedy about notorious serial killer, John Wayne Gacy. During the '70s, Gacy brutally murdered at least 33 young men. Without nuance or substance, Clive Saunders's film celebrates Gacy's legacy.

During his reign of terror, Gacy sidelined as a party clown, which features prominently in the movie. Gacy does little to provide insight into the man's mind. Its gruesome tone borders on that of an exploitation film.

Best: Hounds Of Love (2017)

Hounds of Love

Hounds of Love is a very difficult film to watch. Anchored by stellar performances from its cast, this Australian drama is based on Perth murderers David and Catherine Birnie. The couple kidnapped, tortured, and murdered two teenage girls and two women in the fall of 1986.

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Ashleigh Cummings gives a gut-wrenching performance as the Birnies' fifth victim, Vicki, who manages to escape. Director Ben Young weaves this endlessly depressing tale with a thread of hope via Vicki's will to survive her ordeal.

Worst: Ed Gein (2000)

Ed Gein

Marketed as a psychological thriller about Wisconsin serial killer Ed Gein, this film from Chuck Parello is totally repugnant. Gein confessed to killing two women in the '50s, but it's estimated the death toll is much larger. Gein is also infamous for exhuming bodies from local cemeteries and doing terrible things with the remains.

Parello's film does little to give audiences insight into Gein's inner workings. Ed Gein, also released as In the Light of the Moon, feels more like a B-movie designed to exaggerate and inflate the life of a very sick man.

Best: Memories Of Murder (2003)

Memories of Murder

Bong Joon-ho's career as a Korean filmmaker spans decades. His latest masterpiece, Parasite, garnered praise all over the world from critics and moviegoers alike. Long before releasing this Oscar-winning feature, Joon-ho directed a fictionalized of Korea's first known serial killer: Lee Choon-jae.

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Memories of Murder relies on spectacular visual imagery and engrossing acting to propel its story. Bong employs his signature satire and dark comedy as well. His frequent collaborator, Song Kang-ho, one of Parasite's stars, plays the detective in charge of solving the murders.

Worst: Karla (2006)

Karla

Another serial killer flop marketed as a deeply psychological look into the mind of evil, Karla focuses on Canadian serial killer Karla Homolka. With her husband, Paul Bernando, Homolka was involved in the deaths of three teenage girls in Ontario, including her own sister.

Laura Prepon plays Homolka in this movie directed by Joel Bender. While it doesn't revel in the gory details of their brutal murders, Karla fails to engage audiences in the title character's motivations. The movie also fails to explore Homolka's complicity in the murders.

Best: Dahmer (2002)

Dahmer

Long before he became an action star, Jeremy Renner played serial killer Jeffrey Dahmer in this underrated feature. The few narrative mistakes made by filmmaker David Jacobson are evened out by Renner's compelling performance.

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Through flashbacks, Dahmer traces the killer's evolution from a troubled teenager into a compulsive murderer of men. Renner manages to portray the complexity of Dahmer's inner psychology with aplomb. In the film, Dahmer develops his own problematic mythology about being a lonely outcast in order to justify his murderous turn.

Worst: Green River Killer (2005)

Green River Killer

Gary Ridgway targeted vulnerable female sex workers and hitchhikers all over the state of Washington between the '80s and '90s. He was caught in 2001, making headlines for receiving 49 murder convictions.

This 2005 low-budget independent feature about Gary Ridgway is a depraved film that revels in depicting Ridgway's approach to picking up and assaulting women. Green River Killer portrays the victims as one-dimensional objects instead of real people. This is definitely a movie to skip.

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