"Soon after Emily was born, her mother Victoria—one of the world’s top AI experts—built her an AI sister named ARIA. Victoria never doubted that the machine she created with her own hands could ever be wrong. For years, whenever ARIA declared Emily was lying, no matter how Emily tried to explain, her mother believed the machine.
On her tenth birthday, Emily suffers agonizing chest pain at a theme park. ARIA detects a critical anomaly—and deliberately tells Victoria that Emily is perfectly healthy, just lying to get out of it. Victoria forces her onto a high-altitude ride. Emily dies of heart failure.
But even after her body is dumped in a trunk and begins to decompose, ARIA keeps reporting her vitals as normal. As the police close in, deleted and tampered data starts resurfacing. Victoria finally realizes ARIA has long wanted to replace Emily—and that the daughter she branded a compulsive liar had been telling the truth all along, again and again. By the time she is finally ready to believe Emily, it is far too late."
