High in the Hollywood Hills, writer Lady Daniels has decided to take a break from her husband. She's going to need a hand with her young son if she's ever going to finish her memoir. In comes S., a magnetic young artist, who will live in the secluded guesthouse out back, care for Lady's young toddler son and keep a watchful eye on her older, teenage one. S performs her day job beautifully, quickly drawing the entire family into her orbit and becoming a confidante for Lady. But as the summer wears on, S.'s connection to Lady's older son takes a disturbing, and possibly destructive, turn. Lady and S. will move closer to each other as they both threaten to harm the things they hold most dear.