Two infamous British serial killers had a lesbian affair in prison, claims one of their lawyers.

Rose West, the “House of Horrors” killer responsible for 10 murders, had become “quite taken” with Myra Hindley a.k.a. the Moors Murderer, who committed the rapes and murders of five children with her partner, Ian Brady, according to West’s former attorney, Leo Goatley.

Hindley, known as Britain’s most notorious female killer, was worried her status would be threatened by Rose’s 1995 conviction, writes Goatley in his new book, “Understanding Fred & Rose West.”

But the two soon warmed to each other, the Daily Mail reported. According to Goatley, West told him: “Yeah, Myra, she’s all right, we get on, I want to see how it goes.”

When Goatley visited West a few months later, her tone had shifted dramatically.

“She was saying, ‘You have to watch Hindley, mind. She is very manipulative. You don’t realize it, but she gets you doing stuff for her. Oh, she’s clever, all right. She’s flippin’ dangerous, that one. She ain’t going to take me for a c*** again.’ And so heralded the end of the romance,” Goatley writes.