The unit receives a call about a wealthy philanthropist ,Claudia Drexler, found murdered in her upscale apartment. Clark and Owen question Claudia's father-in-law Marvin, a shipping mogul, who explains that he reported the murder after his son Nathan asked him to check on her since he was out of town at a conference. They learn from Nathan that Claudia, a recovering addict, founded a drug treatment center and would give some of the residents a second chance by hiring them to do odd jobs around the apartment. They question drug counselor Andrea Gundersen for possible suspects and she tells them that resident Edward Rodrigue had access to Drexler's apartment, but his alibi holds up. After looking through Claudia's past emails, they discover that Marvin and his P.I. Lyle Creasman had sent her threatening messages to get her to stop spending the family's money on rehabilitating junkies. They analyze Creasman's surveillance files to determine that Claudia visited Andrea Gundersen the night she was killed. When they arrive at Andrea's house, they catch her in the middle of a drug deal and she admits to dealing to Nathan. Nathan' alibi falls apart when no one can place him at the conference and surveillance shows him entering the building near the time of Claudia's death. The change in his outfit leads them to look for bloody clothes in the apartment and they find charred clothing remains on the outside grill, but confronting Nathan incites him to lawyer up. Clark and Owen follow Nathan knowing that his high is wearing off and eventually track him into an alley looking to score. Nathan confesses that he killed Claudia when she begged him to stop using and threatened to go to his father which would eventually cut off the money supply. Arroyo's wife Lorraine asks Mckenzie to teach her how to shoot a gun so that she can better connect with her husband. Owen helps Clark deal with a loan shark who is harassing his mother Nora who is late on a her loan payment and assuages his fears about his juvenile record. We learn that when Clark was a kid he lied on the stand to protect his father from being convicted of murder. The Mayor takes an interest in Clark after he hears about Clark's brazenness with Marvin.