READING up on the crimes of Charles Manson was a journey to the dark side for Claire Holt.
The Brisbane-born actress, who was born nearly two decades after Manson's infamous murders, stars opposite David Duchovny in the new US crime drama Aquarius.
Airing exclusively on Presto in Australia, the series follows police officers Sam Hodiak (Duchovny) and Brian Shafe (Grey Damon) as they track cult leader Manson before his 1969 killing spree.
"I spent a lot of time Googling and reading and asking people who were around at that time," Holt told APN.
"It was something I definitely had to learn more about and as I did it was frightening. I had to stop reading about it at night time."
The 26-year-old plays police officer Charmain Tully, who finally gets away from the desk when she volunteers to go undercover with Shafe to infiltrate the Manson Family.
Gethin Anthony, who played Renly Baratheon on Game of Thrones, plays Manson.
"Gethin does such an amazing job of it," Holt said.
"He really made it his own. He wasn't trying to copy Charles in any way."
The role is a new turn for Holt, who has made a name for herself in the supernatural genre in H20: Just Add Water, The Vampire Diaries and The Originals.
Next month she will begin filming the thriller 47 Meters Down in London and the Dominican Republic.
She plays Mandy Moore's sister in the film, which follows two sisters who become trapped in shark observation cage during a Mexican vacation.
"The water is something I'm very familiar with after H2O," she said.
"It should be really fun. It's exciting when you're trying to shoot drama underwater.
"Mandy's awesome. We just did scuba training together and she's such a sweetheart."
The first season of Aquarius debuts on Presto tomorrow.
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