Judge Grove is back as Sykes testifies.

In flashback, we see the discovery of a body, shot execution style. The victim had security clearances.

The action jumps back and forth between the trial and the investigation.  In the early part of the investigation, the victim's wife explains that they had a keyless entry to their home using an app on their phone called Offkey. They had to log into the app. If a new device accessed the app, the wife would get a notification from Offkey but she got no such notification on the day of the murder.

The wife thinks her ex-husband was the murderer. He and his son were vacationing in the Catalina Islands, but it was possible that he logged into Offkey from there and sneaked back to do the murder.

Through flashbacks, we learn that Major Crimes spoke to both the ex-husband and the teenage son, Danny. They both seem shocked that Tom is dead, and Danny states that he hated his stepfather for breaking up his parents' marriage. However, he says his dad used his cell phone and the detectives accuse Richard Blum of the murder.

During the trial, Linda Rothman asks for a mistrial. It seems Sykes downloaded the Offkey App on her phone.

In flashback, we learn that Sykes was consulting with Mark Hickman again and that he convinced her to download the app so he could see how it worked. In the judge's chambers, Rothman won't reveal her source and Sykes believes it was Hickman. The judge rules in favor of Major Crimes, but Hobbs thinks their case is sunk anyway.

Sykes confronts Hickman who initially denies telling Rothman. Sykes tells him never to contact her again.

Major Crimes continues the investigation to try to make their case stronger. After Sykes records another conversation with Hickman on her phone, they realize that Blum's brother Paul was involved in the murder. They convince Paul to confess and then bring him to court, where he and his brother have it out and the judge threatens to send both of them to solitary.

Amy flirts with Hickman, sort of. Meanwhile, Julio's foster son reappears.