In July 2007, a joint birthday celebration for a 6-year-old and two 18-year-old girls draws a crowd of 50 to a Toronto community backyard on a warm summer day. As night falls and the cake is cut, the atmosphere shifts quickly as tensions escalate, leading to a violent gun battle that results in the death of 11-year-old Ephraim Brown. Detectives investigate the tragedy, uncovering that Ephraim, lost in his music, likely didn't hear the warning to run. They also learn that the birthday girls unknowingly invited two rival gangs to the event, setting the stage for the deadly confrontation.