Lilya Chernova is a Russian teenager and operative for the Ekaterina branch of the Cahill family. Lilya is the daughter of two high-ranking Russian Ekaterina agents, Vladimir Chernov and Vera Chernova. She is the best math student in her school's academic history. However, Lilya's passion is for fashion, which fits with at least two the Ekaterina strengths, including inventing and designing. Some people call her outfits strange, (Natalie Kabra says they're "vomit-inducing") but Lilya knows that her critics just lack imagination. This means Natalie must know of her or has even contacted her. As it says in The Black Book of Buried Secrets, 'it takes a special person to wear a green sequined dress and magenta cowboy boots to a math competition.'
She is mentioned in the Ekats' agent section. She does not appear in the rest of series.
Her main card is Card 24: Lilya Chernova.
She appears in Mission 3: The Lost Diamond.