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Zac Efron: Ted Bundy -

Zac Efron took on the role of Ted Bundy for the movie 'Extremely Wicked, Shockingly Evil and Vile' (2019). Bundy claimed at least 30 lives and used his good looks and charm to gain the trust of his victims. This made the handsome Zac Efron the perfect choice to play him.

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Zac Efron: Ted Bundy -

Efron lost 13 pounds (six kg) to mimic Bundy's reedy physique. For his character research, he spent time studying the famous serial killer's personality and mannerisms. He was disturbed to discover that he and Bundy had more in common than one would expect.

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Zac Efron: Ted Bundy -

Efron said that he and Bundy carry themselves in a similar way. He described Bundy as well spoken and bashful, often hiding his anxiety behind a smile. Efron found that he saw past the murderer to the human being. He described it as a "mindf*ck."

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Darren Criss: Andrew Cunanan -

'Glee' may be one of the least murdery shows in the history of television, but actor Darren Criss managed to make the transition from a cappella singing school boy to serial killer quite seamlessly.

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Darren Criss: Andrew Cunanan -

In 2016, Criss starred as serial killer Andrew Cunanan in the hit show 'The Assassination of Gianni Versace: American Crime Story.' Andrew Cunanan famously went on a killing spree in 1997, ultimately murdering fashion designer Gianni Versace.

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Darren Criss: Andrew Cunanan -

Criss said his acceptance of the darkness within himself allows him to be a happy, light-hearted person in his own life, but it also allowed him to acknowledge the humanity within a murderer like Cunanan. This came through in his disturbing yet sympathetic portrayal of the troubled young man. As a result, he won a Golden Globe and Emmy for the role.

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Charlize Theron: Aileen Wuornos - Charlize Theron took on the role of Aileen Wuornos for the 2003 film 'Monster.' Wuornos is one of the most notorious female killers in recent history. She killed seven men in Florida between 1989 and 1990.

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Charlize Theron: Aileen Wuornos - Aileen Wuornos' arrest and trial were highly publicized, and she conducted a series of interviews from prison, so Theron had a great deal of footage to study. Wuornos was an extremely complex character who demonstrated intense mood swings and emotional instability.

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Charlize Theron: Aileen Wuornos -

In interviews, Theron said that she picked five common physical gestures exhibited by Wuornos and perfected them. She learned to add a waddle to her walk, widen her eyes when things got intense, and carry her tension in her mouth. For her efforts, she won the Academy Award for Best Actress.

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Jeremy Renner: Jeffrey Dahmer -

Long before his days as an Avenger, Jeremy Renner played the infamous serial killer Jeffrey Dahmer in the 2002 film 'Dahmer.'

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Jeremy Renner: Jeffrey Dahmer - Dahmer murdered 17 boys and young men over a period of 13 years, and was known as the "Milwaukee Cannibal" for obvious reasons. Renner has always found acting therapeutic, as it allows him to express emotions like rage and sadness in a safe way. However, his experience playing Dahmer pushed this to the edge.

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Jeremy Renner: Jeffrey Dahmer -

Renner revealed that he had to let himself go to some scary places within himself in order to relate to Dahmer's darkness. It was challenging, but he allowed himself to take full advantage of the opportunity to explore this side of himself.

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John Cusack: Robert Hansen - John Cusack played Alaskan serial killer Robert Hansen in the 2013 movie 'The Frozen Ground.' Hansen was known as the "Butcher Baker" because he lived a seemingly normal life as a family man and baker for more than a decade while secretly murdering at least 17 women.

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John Cusack: Robert Hansen -

Cusack said he was very wary of taking on such a dark role. He accepted the part but found Hansen a very challenging character to play and said that such a role can leave lasting effects.

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John Cusack: Robert Hansen -

While studying Hansen, Cusack came to the horrible conclusion that he was having a good time while hunting his victims. In playing such a character, Cusack felt he was testing himself by going to "the other side" and seeing if he could come back without going crazy or becoming a psychopath himself.

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Michael Shannon: Richard Kuklinski -

Michael Shannon played Richard Kuklinski in the 2012 film 'The Iceman.' Kuklinski is unique as a serial killer because killing was his career, and the sheer number of lives he claimed is staggering. In the nearly 40 years he worked as a hitman, he killed somewhere between 100 and 250 people.

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Michael Shannon: Richard Kuklinski -

Kuklinski conducted extensive interviews with HBO while in prison. Shannon studied the 20 hours of footage and discovered how complicated Kuklinski was. Despite the atrocities he committed, he did seem to live by a code. He didn't kill women or children and knew that if he didn't kill one of the men on his list, somebody else would.

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Michael Shannon: Richard Kuklinski -

Shannon also discovered that at his core, Kuklinski was a very sad and lonely man who lived most of his life in pain.

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Steve Railsback: Charles Manson -

Steve Railsback starred as Charles Manson in the 1976 TV movie 'Helter Skelter.' It was one of the first significant portrayals of the cult leader after the 1969 murders, and was the defining role of Steve Railsback's long career.

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Steve Railsback: Charles Manson -

Railsback prepared to play Manson by watching documentaries and studying books written about him. He tried to get himself into the mindset that Manson's philosophies and actions were right, because naturally that's what Manson himself thought. He had the choice to go and meet Manson in prison, but chose not to as he was scared of being manipulated by the notoriously charismatic killer.

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Steve Railsback: Charles Manson -

Railsback even went home after shooting and locked himself in a closet to get the feeling of solitude that had shaped Manson's life (Manson had been in and out of correctional facilities since the age of 11). Railsback's performance was so convincing that some say he has the scariest eyes in the industry!

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Michael Rooker: Henry Lee Lucas -

Michael Rooker starred in the 1986 film 'Henry: Portrait of a Serial Killer' as Henry Lee Lucas. Lucas has been called the "Confession Killer" because he confessed to more than 100 murders, although he was only convicted of 11.

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Michael Rooker: Henry Lee Lucas -

Lucas caused mayhem with his confessions because investigators all over the US had to come to interview him and verify his claims. Rooker studied the hours and hours of interview footage and concluded that Lucas was "full of sh*t." Despite that, he did manage to pick up a great deal about his speech and body language.

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Michael Rooker: Henry Lee Lucas -

While filming the movie, Rooker would disappear into a private room between scenes where he could be alone and avoid breaking character.

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Ross Lynch: Jeffrey Dahmer -

Ross Lynch is another actor who played Jeffrey Dahmer. He was cast as a young Dahmer for the 2017 movie 'My Friend Dahmer,' which focuses on his early life. Lynch developed a lot of empathy for Dahmer, who started out as a lonely gay kid trying to hide his sexuality and the dark impulses that were starting to emerge.

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Ross Lynch: Jeffrey Dahmer -

Filming was an intense experience, as they had access to Dahmer's real childhood home for their set. Lynch found that getting into character wasn't difficult, it was getting out of Dahmer's head at the end of the day that was hard. He would go home and take long showers to "shed" Dahmer every night.

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Damon Herriman: Charles Manson -

Damon Herriman has played Charles Manson not once, but twice. He got the role in the popular Netflix series 'Mindhunter' and Quentin Tarantino's hit movie 'Once Upon a Time in Hollywood' (2019). The filming for each project took place only weeks apart, but approached Manson at very different times in his life and very different ways.

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Damon Herriman: Charles Manson -

Herriman spent six months going down a Manson rabbit hole to prepare for 'Mindhunter.' He said he studied every written, audio, and visual source on Manson he could find. In his words, Manson didn't "infect" him, but he did start to understand his influence.

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Damon Herriman: Charles Manson -

Even after his extensive research, he felt that he didn't know who Charles Manson was, and believed that Manson didn't know himself either.

Sources: (News Week) (Variety) (Rolling Stone) (Ranker)

See also: The creepiest actors of all time

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