After the brutal murder of their teenage daughter Aarushi, Rajesh and Nupur Talwar's hopes for swift justice crumble as the prime suspect Hemraj, the family servant, is found dead on the roof terrace of the family home. Under intense media scrutiny, the local police scramble to find the culprit, eventually leading them, after many twists in the case, to arrest the grieving father. What appears to be a botched local police investigation into the double murder forces authorities to replace the police with India's elite investigative unit – the Central Bureau of Investigation (CBI). But when the CBI clears Rajesh of the killings, the investigation's focus swings back to nearby servants and staff, escalating social and class tensions in Noida, India.

A new lead investigator reinvigorates the stalled CBI investigation, who switches track by putting focus back on the parents in what he believes may have been honor killings. Despite little hard evidence and increasingly desperate legal battles, Rajesh and Nupur Talwar eventually find themselves charged with the murders. After more than nine years and three investigations, the parents win their appeal, but troubling questions remain over what really happened the night Aarushi and Hemraj died.