Chelsie Preston Crayford and Danielle Cormack, who play brothel owner Tilly Devine and vice queen Kate Leigh respectively in the Australian crime series, said that both women had "hard" lives that made them follow such "terrible" paths.
Preston Crayford told New Idea magazine: "[Tilly] did terrible things - but my job as an actress isn't to judge, it's to empathise with her so I can bring Tilly to life as vividly as possible.
"Tilly was a girl of the London slums. Her major motivation in life was class - she started on the bottom rung in abject poverty and didn't rest until she was at the very top and sitting pretty."
Cormack added that she went to visit Leigh's grave at Sydney's Botany Cemetery in order to bond with her character more, saying: "It was a private moment, a chance to pay my respects before I walked in her shoes and put myself in the situations she faced in her life.
"I believe we're all a product of our environment and Kate's early life was very, very hard."
The two actresses recently revealed that they grew "incredibly close" during filming, despite their characters being bitter rivals. Preston Crayford also said that the late Amy Winehouse inspired her portrayal of Devine.
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