New from Sarah Pekkanen, the #1 New York Times bestselling author of House of Glass and co-author of The Wife Between Us.

A shocking psychological thriller about the complex bonds of sisterhood-and what happens when they are stretched to the breaking point, The Locked Ward "will leave you guessing until the very end" (Jeneva Rose, bestselling author of The Perfect Marriage).

Some doors should never be opened.

Was it bitter, all-consuming jealousy? Pathological sibling rivalry? Pure insanity?

Whatever the cause-and everyone has a theory-it's the Crime of the Decade when glamorous Georgia Cartwright, who was adopted as a newborn, is accused of killing the biological daughter of her wealthy, Southern family.

Georgia is locked in a psychiatric institution where the most violent offenders are held while she awaits trial. The only words she whispers when her estranged twin sister Amanda visits are, "I didn't do it. You've got to get me out of here."

Amanda doesn't trust Georgia, but she can't abandon her in a place so eerie and menacing that it seems to exist in another dimension. Is Georgia the victim of a powerful family that's so depraved murder is the least of their crimes? Or is Amanda being led down a path of madness into the web of a master manipulator?