"A cool, contemporary, whip-smart thriller." -- --Paula Hawkins, author of The Girl on the Train

She could be the most dangerous person in the room...

From her first day as Personal Assistant to the celebrated Mina Appleton, Christine Butcher understands what is expected of her. Absolute loyalty. Absolute discretion. For twenty years, Christine has been a most devoted servant, a silent witness to everything in Mina's life. So quiet, you would hardly know she is there.

Day after day, year after year, Christine has been there, invisible--watching, listening, absorbing all the secrets floating around her. Keeping them safe.

Christine is trusted. But those years of loyalty and discretion come with a high price. And eventually Christine will pay.

But it would be a mistake to underestimate such a steadfast woman as Christine. Because as everyone is about to discover, there's a dangerous line between obedience and obsession.