Emotional Proximity
Knowing that the fire at a rave that killed or injured several kids including Alvin's daughter, was deliberately set, Intelligence is tasked with finding the one responsible. They start with a known arsonist but it's not him. Later they learn that the owner had a heated conversation with a guy and bring him in. He denies doing it. But then one of the victims says she knows who set the fire and tells them what she knows. They find the man and bring him in. Alvin joins them because his daughter died.
