"I was having pretty horrible dreams." 7 actors on what it was like to play a serial killer.

This post mentions sexual assault and violence and might be triggering for some readers.

Playing a real-life person is a challenge for any actor.

But when that person is one of history’s most notorious serial killers, things can be a bit more difficult. 

Not only is there a lot of research involved to prepare for the role, but sometime actors have to deal with the consequences of playing a dark character even after they leave the set. 

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But that hasn’t stopped actors of the likes of Zac Efron, Charlize Theron and David Tennant from taking up the challenge.

Here's what seven actors said about their experience playing a serial killer. 

Zac Efron as Ted Bundy.

Image: Netflix/Getty.  Zac Efron took on the role of American serial killer Ted Bundy in Netflix's Extremely Wicked, Shockingly Evil and Vile last year. Bundy was one of the most notorious criminals of the late 20th century, who was responsible for the murders of at least 30 women in America during the 1970s – many of whom he raped before killing. 

Speaking to Entertainment Tonight, the High School Musical actor said the role was "fun" to play and gave him a chance to experiment.

"[The film] simply tells a story and sort of how the world was able to be charmed over by this guy who was notoriously evil and the vexing position that so many people were put in, the world was put in. It was fun to go and experiment in that realm of reality."

When it came time to prepare for the role, Efron watched real-life footage of Bundy during his trials and spent two weeks in an abandoned prison, where he later filmed a nude scene for the film. But it didn't take long for Efron to notice a few similarities between him and the serial killer. 

"Something clicked pretty early on, and it was kind of scary. It was that Ted and I had quite a bit in common in the way we carried ourselves. There are a few mannerisms," he told Variety.

"You can tell he's a bit bashful. He's kind of shy. He's a well-spoken guy, but he hides his anxiety with a bit of a smile. I didn't want to do too much of an impersonation."

Charlize Theron as Aileen Wuornos.

Image: Denver and Delilah Productions/Getty. Charlize Theron took home an Oscar for her portrayal of American serial killer Aileen Wuornos in the 2003 film Monster. Wuornos was a sex worker who killed at least seven men in Florida between 1989 and 1990. She was later executed by lethal injection in October 2002. 

To play Wuornos, the South African actress had to gain weight and learn how to walk and talk the way Wuornos once did.

"I was lucky enough to have a lot of footage of Aileen, and I just watched it constantly. I watched her behaviour; I would spend a lot of time in front of the mirror, mimicking her, just trying to pick up maybe five things she kept doing constantly and trying to get comfortable with them," Theron told The Telegraph. 

"She had a waddle, so that was kind of easy, and when she got intense her eyes would get really big, just the opposite of some people. And she carried all her tension in her mouth whereas I carry mine in my forehead."

Speaking to About Film, the 45-year-old explained that playing Wuornos was emotional, and she had to “get to a place of understanding” when filming. 

"She was a normal human being that had gone through a lot of heartache. I related to that on a different level. I think you have to get to a place where the best you can do is understand - maybe - why, and then really drag yourself through it, because it's tough to do those things. The last killing, it was impossible. It was one of the worst nights of my life."

David Tennant as Dennis Nilsen.

Image: Stan/YouTube. 

Earlier this year, David Tennant played Scottish serial killer Dennis Nilsen in Stan’s true-crime miniseries Des. 

For those who haven’t seen it, Nilsen murdered at least 12 young men and boys in London and attempted to kill seven others between 1978 and 1983.

Known as the Muswell Hill Murderer, Nilsen typically met his victims – who were largely homeless and/or homosexual men – in bars or on public transport, before inviting them back to his home with the promise of alcohol an d shelter. 

To prepare for the role, the Dr Who actor told The Guardian he watched documentaries and footage of Nilsen. 

“He also wrote a very extensive self-indulgent autobiography, which I read some of, as well as rereading Masters’s book and looking at billions of articles.” 

But Tenant said there was more to his research than just trying to “replicate the way [Nilsen] talked or the way he moved”. 

“It’s not just about impersonating a character. It’s about trying to get some sort of sense of him, not to relate to why he did what he did but to try to understand it. And it’s particularly hard with Nilsen because he’s someone who has written a lot about himself – but it doesn’t all tally up, so you have to find a space where all the things he said and all the things that other people have said about him can be true.”

Dominic West as Fred West.

Image: ITV/Getty.   Dominic West played English serial killer Frederick West in the ITV drama series Appropriate Adult in 2011.

Fred tortured, raped and murdered 12 young women between 1967 and 1987, the majority with his second wife, Rosemary. Most of the murders took place at their Gloucester home which became known as the ‘House of Horrors’. Fred later committed suicide after being charged with the murders.

Dominic told The Telegraph he ended up having nightmares while playing the serial killer.

“I was having pretty horrible dreams during the shoot where I’m perched on a wall and Fred West is trying to grab me and pull me down,” he explained.

“I only did it for three weeks and it was a pretty intense, very dark three weeks. It was grim.” 

The 51-year-old actor also didn’t see his children for seven weeks while filming in order to immerse himself in the role. 

“My children were a brilliant way of escaping Fred West at the end of filming and when I came back it made it all the easier to eradicate him from my consciousness,” he told Express.

“But had they been around when I was filming I don’t think I would have been so easily able to act him. It was only possible in a finite, brief period away from home when I could completely concentrate on the role and immerse myself in it.”

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Jeremy Renner as Jeffrey Dahmer.

Image: Peninsula Films/Getty. Back in 2002, Hawkeye actor Jeremy Renner took on the role of Jeffrey Dahmer in the 2002 film Dahmer. Also known as the Milwaukee Cannibal or the Milwaukee Monster, Dahmer was an American serial killer and sex offender who murdered and dismembered 17 men and boys between 1978 to 1991. He was eventually charged and sentenced to 16 life terms, but was killed by a fellow inmate in prison in 1994.

After playing the role of Dahmer, Renner started to notice some unusual things happen in his personal life.

"After I did the film, playing a guy who was basically a monster, things started getting creepy," he told Parade in 2009.

"My cat was stolen. Then some girl bit me in a bar because I wasn’t paying attention to her anymore and I had to go to the hospital. It kept me single for a while, that’s for sure. Lot of people I wanted to date, but people I probably shouldn’t date.”

Cameron Britton as Edmund Kemper.

Image: Netflix/Getty. Cameron Britton earned himself an Emmy nomination for Outstanding Guest Actor for his breakout role as Edmund Kemper in Netflix series Mindhunter. Kemper was an American serial killer, rapist, cannibal and necrophile who murdered 10 people during the 1960s and 1970s. 

Speaking to Variety in 2018, Britton explained that he had never heard of Kemper before reading the script. 

"I looked up his name and found him on YouTube and went from there. Every single thing that I have learned about him since has been unendingly fascinating to me,"  said Britton.

When it came time to film, Britton said that he and his cast mates would sing songs on set to lighten the mood. 

"Mostly between takes [Jonathan] Groff and Holt [McCallany] and I were singing show tunes. It was a really dark subject matter, so it was really nice to have light, fun energy between to remember that this is acting."

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However, even after filming, Britton would sometimes find it hard to let go of the character.

"Sometimes Ed just lingers. It’s hard to get out of that energy," he told the publication. 

"That’s the hard part — with many characters I’ve done, sometimes I feel them sprout up when I’m driving and I want to do them, but with Ed I ignore those impulses because if you just have dark thoughts all day, they become habitual. But that being said, I very much enjoy that headspace because, creepy as it is, there’s a control and a power that comes from being this monster."

Damon Herriman as Charles Manson.

Image: Getty/Sony Pictures/Netflix. Aussie actor Damon Herriman played cult leader Charles Manson not once but twice last year. 

The 50-year-old played Manson in Quentin Tarantino’s film Once Upon a Time in Hollywood before reprising the role in the second season Netflix’s Mindhunter, where he played an older version of him.

To prepare for the roles, the actor spent a lot of time researching Manson, whose followers carried out several murders in the late 1960s.

"I watched every feature version I could find, every documentary, every interview several times, read a couple of books, listened to some podcasts. I was trying to get as much information as possible, mostly just trying to soak in the visuals and the sounds of the guy," he told Vulture last year.

But it was the research that Herriman found most disturbing. 

"The actual playing of Manson, certainly in the Mindhunter scene, it’s him in jail. He’s locked up, he’s ranting. That’s not the disturbing part," he told Variety earlier this year.  

"For me, the disturbing part is doing the research of what actually happened over those two nights [when Manson’s followers murdered seven people]. It didn’t matter how many times I’ve read about it or watched the documentary describing it, it absolutely chilled you to the bone to think what those people went through."

After the two performances, the actor said he would like to move on from playing Mansion.

"I think twice is quite enough."

If this post brings up any issues for you, or if you just feel like you need to speak to someone, please call 1800 RESPECT (1800 737 732) – the national sexual assault, domestic and family violence counselling service. It doesn’t matter where you live, they will take your call and, if need be, refer you to a service closer to home. 

You can also call safe steps 24/7 Family Violence Response Line on 1800 015 188 or visit www.safesteps.org.au for further information.

Feature Image: Netflix & Stan.