Harry Bosch finds out one of his old cases is up for review and worries that all the cases since might be questioned. In another part of town, thugs in masks murder a pharmacist.

Louis Degner brings Bosch (as Dominic Reilly) to the Garcia Pain Clinic, where Bosch is surprised to be examined by none other than Dr. Hansen from the VA. Hansen sees Reilly as nothing more than a pathetic addict. He gives Bosch a few pills and sends him home, saying they'll be in touch when it's time for Bosch to repay the favor. Seeking answers to his CI's killing, Edgar follows up with Gary's old gang contacts - men who spent time in jail after Gary flipped on them following a robbery 20 years ago. Robertson and his team search a warehouse where they find the pharmacy killers' getaway car and a link to the shell company that owns the shill plane - Western Sandblast. Hoping to rattle someone into making a mistake, Bosch visits Borders in prison while Bonner confronts Rita on the outside. Borders' cocky demeanor changes when Bosch lets him know they've been talking to his wife. Maddie, finding herself emotionally drawn into a rape victim's trial, considers the intricacies of justice, as Barrel considers Billets' suggestion that it's time to retire. Bosch updates Chief Irving on the Borders case. Bosch believes Olmer's attorney, Lance Cronyn, stealthily obtained Olmer's DNA during one of his many visits. After Irving provides Bosch with video from the LAPD property room where a key piece of evidence was handled, Honey Chandler and Bosch figure out how Olmer's DNA was then planted by a property clerk named Spencer. While weighing an opportunity to run for Mayor, Irving provides DA Hines with a potential alternative bringing criminal charges in the officer-involved shooting. CIU Investigator Henry searches for evidence to back her belief that Bosch planted the seahorse pendant to frame Borders -- just as Irving shreds a document involving the very same evidence.

A detail from Kent's widow Alicia leads Bosch and the FBI to suspect a group of Sovereign citizens in connection to the stolen radioactive cesium and Overlook murder, but they clash over tactics, causing a deadly standoff.

When cops discover the body of a homeless man covered in radiation burns, the hunt for the cesium intensifies but Bosch and Edgar wonder if their assumptions about the crime have been wrong all along.

Bosch is pulled away from the arson case to a double homicide in the Hollywood Hills and finds RHD Detective Jimmy Robertson on the scene. When the harassment of Lt. Billets escalates, Captain Cooper and Lt. Thorne are angry that she reported it to IA instead of talking to them. Maddie makes a shocking discovery. Bosch and Edgar try to get Alvarez to talk.

After discovering Alvarez has been transferred, Bosch enlists Chief Irving’s help. Pierce and Vega get a lead on the hitman. Billets reaches out to a former Hollywood cop for intel on Leonard and Norris. When Bosch and Edgar meet with Carl Rogers, Edgar lets a detail of the case slip, enraging Bosch.

Robertson and Bennett follow the hitman's trail to Las Vegas, hoping to find a connection to Fowkkes' other clients. When Billets performs a security evaluation at a local jewelry shop, she gets more than she bargained for. Irving gives Bosch an order, causing Bosch to lose faith in the system he has defended his entire career.

As Billets posts the Hollywood homicide detectives' new assignments, Bosch puts a plan in motion to arrest Mickey Peña, leading to some severe consequences. Billets makes an impression and Maddie makes a decision about her future.