If she had gotten better grades in school, Mimi Keene says, she’d now be a vet instead of an actress. The 26-year-old shares her home in Hertfordshire, England—just down the road from where she and her brother grew up—with three dachshunds, a Chihuahua, and a blue-point Siamese cat named Darling, who purrs loudly on Keene’s lap for the entirety of our conversation. Becoming an actress, Keene says, was “a happy mistake.”

Keene’s animal-loving, homebody nature (“I’m a creature of habit—I get very comfortable in my routine,” she says) might surprise viewers who know her as Ruby Matthews, the icy queen bee of Moordale Secondary School on Netflix’s Sex Education. The contrast between actress and character is even more stark in Keene’s latest role—she plays the mysterious femme fatale Kay Elliot in a new series adaptation of Agatha Christie’s Towards Zero, alongside co-star Anjelica Huston.