Later, when she tried to remember the moment everything unravelled, she'd think of the body at the bottom of the stairs--shocking, silent, and terrifying.After discovering her husband Jason's latest affair, Alice knows their marriage is over. But Jason refuses to walk away from their children--or their home. So they strike a desperate deal: they'll keep the house, taking turns living there. Half a week each. Simple.But the arrangement quickly becomes suffocating. Each time Alice returns, her space has changed--Jason's mess taking over, her belongings misplaced.And Alice can't shake the feeling she's being watched, by someone who tracks her moments alone. Is Jason playing mind games? Or is someone else?As her grip on reality spirals, Alice begins to wonder if the end of their marriage might be the end of her.