When a caretaker reports her 63-year-old cancer patient missing, Detectives Ayanna Corbin and Mike Cochran learn the woman has left behind a 15-year-old son. Detectives sift through false sightings, deceitful witnesses and a missing mattress to solve a mystery in which nothing is as it seemed to be.

Detectives Laura Skrip and Joe Struck hunt for a man after his family receives a threat to his life. They must sort through the missing man's troubled family situation and possible drug connections. Next, during a summer of gang violence on Chicago's streets, Detectives Mario Gonzalez and Hector Crespo search for a teenager with a rare sleep disorder. He vanished after getting into a fight with a group of boys. Detectives race to find him before he becomes another casualty.

Detectives Pam Childs and Selles Morris search for a 14-year-old girl who has been snatched by a 19-year-old with possible gang connections. The hunt leads detectives to a hotel district at the edge of town, through gang territory and across the state. Meanwhile, on the hottest day of the year, Detective Pat Riley searches for a missing 66-year-old man with serious neurological problems. Riley fears the man may be armed. The clock ticks as the thermometer tops 100 degrees. Riley must find the missing man before he succumbs to the heat--or gets into real trouble.