Nook’s family thinks they know who killed him. But when the Baltimore police agree to show his mother the surveillance video that captured his final moments, a new story emerges.

Nook’s mother, Toby, had long ago lost faith in the Baltimore police. And as the department tried to repair its public image, a corruption trial exposed the depths of misconduct: An elite group of officers had been stealing from residents for years.

Nook spent the first few years of his life in an affluent suburb of Baltimore. But the city drew him back, and he became part of a young generation caught between the crack epidemic and the aggressive police tactics meant to fix the problem.