On the Oct. 1 episode of "The Mob Doctor," Grace finds her world turned upside down by a hit-and-run incident. A family of four was hit by a drunk driver in a red SUV: The mother has brain damage with blood on her brain, the dad has a dislocated hip, the son has an injured leg, but the daughter appears to be okay. While Grace is treating the little girl, though, she dies suddenly: Her aorta was transected, and there was nothing anyone could have done to save her.
Right after the little girl dies, Grace gets a call from Constantine to come patch up one of his guys. Grace quickly realizes that the injured man was in a car accident, and after asking around, she learns he drives a red SUV.
The injured man is working with Constantine and is revealed to be Captain Patrick Shaw of the Chicago PD, head of the gang task force. He's working on something big with Constantine, which is the only reason Constantine needs him alive. Grace sews him back up and says he's fine, but she's lying. Shaw is bleeding internally and has about 24 hours before he goes critical. Grace just wants him to suffer for killing that little girl.
Meanwhile, Grace's boyfriend is treating the son of the car crash family. He's a soccer player with great talent, but because of injuries sustained in the crash, he might lose his leg. The hospital recommends amputating the leg, but Grace's boyfriend suggests a risky alternative: a graft in an artery that would restore blood flow to the leg, but could cause a nasty infection. They do the graft, but it ruptures. Thankfully, they are able to save the boy's life.
The icing on the cake comes when the boy's mom finally wakes up. Grace brings Shaw over to the mom's room so that Shaw can see her break down when the she learns that her daughter is dead. The hope is that he'll understand the impact of his actions.
Elsewhere, Grace has leaned that Nate is working for Constantine and begs her mother to intervene. Grace's mother confronts Nate, and she also confronts Constantine and tells him to stay away from her family. Constantine has no intention of listening to her, and just a few scenes later, Constantine and Nate are looking over a haul of stolen electronics.
A stolen TV later shows up at Grace's mom's house, which infuriates Grace. She gets even more angry when she learns that what Shaw was doing for Constantine was less about cleaning up the streets and more about getting revenge on Marcellus Coin, the man whose testimony put Constantine behind bars. Grace tells Constantine that she will give Shaw's medical records to the police.
In a final twist, Moretti is revealed to still be alive -- not what Constantine believes. Moretti tries to kill Constantine with a car bomb, but it fails.