It's all hands on deck when a coed named Dawn Cofield is murdered in her dorm room. The victim was dating Pup Clemmons, a former street acquaintance from Stone's undercover days. The thug claims he was in love and is genuinely rattled when Stone tells him Dawn was raped. It's possible that Pup's drug rival, Alex Caldwell, killed Dawn to send a message. But the team finds Caldwell strung up dead in his apartment.
Dawn went to a party the night she was murdered. It was at the Grosse Point home of the prominent McCord family. The rape may have occurred at the bash thrown by Dawn's poly-sci classmate, Brett McCord, who basically admits he sexually assaulted the victim but alibis out for the murder. The team suspects his politically-connected mother, Barbara, may have had motive for the killing once she learned of her son's actions.
Stone's ex-girlfriend, Riley, has been hanging around the station. Sanchez suspects she may be playing him. Eventually, Stone starts to believe that, too. He tells Riley he never wants to see her again. The hits just keep on coming when Stone learns that Pup Clemmons is actually a fed with the DEA. The guy was also truly in love with Dawn while on the job. If anyone can empathize with Pup's situation, it's Detective John Stone.
Amir Sakhani has been funneling drugs across the border into Detroit. Pup says this is the guy who killed Alex Caldwell. He also told Amir that Stone was a crooked cop as part of a ruse. Now the meanest drug dealer in town wants Pup and Stone to be on his payroll. This is their chance to take the guy down for good.
Stone admits that he's a little rusty when it comes to undercover work, so he appears caught off guard when Pup tells Amir that the cops think he's DEA. BANG! BANG! BANG! Pup guns down Stone to prove himself to Amir, who cops to killing Alex Caldwell. Moments later, sirens and flashing lights fill the air in a massive police raid as Pup pops Amir in the chops. As for Stone, he's still smarting from the bullets that pierced the blood packets attached to his bulletproof vest.
Back at the station, Fitch interrogates Barbara McCord. He doesn't believe the woman went to the dorm to kill Dawn. She intended to buy her silence regarding Brett's rape to keep the family name in good standing. Things went south and she trashed the room to make it look like the murder was done by her drug dealer boyfriend. A missing stone from Barbara's diamond ring was found at the crime scene. Washington says, "If the diamond fits, you can't acquit."
Longford's a little off his game after getting word that his daughter got engaged to a guy she's only known for six months. Eventually, he extends an olive branch by offering to have his future son-in-law over for dinner. Of course, he'll run a background check on the guy first. Washington's also been a bit on edge as he awaits his first evaluation from Fitch. It's all pretty good stuff, though Fitch never mentioned that all day.
Sanchez tends to Stone who is recovering at home with some bruised ribs. He's in pain, but somehow manages to muster up enough strength to take Ariana into the bedroom. When Stone heads out of the house the next day, Riley is waiting for him. She needs money and there's still a huge street bounty on her former lover's head.
BANG! BANG! BANG! Riley guns down Stone. Sanchez hears the commotion and shoots Riley dead. She rushes to Stone's side. Sadly, the red stains on his shirt haven't come from blood packets this time. Sanchez begs Stone to stay with her. Help is on the way. But we fear that when it arrives, it may be too late.