The Devil You Know (Person of Interest)

"The Devil You Know" is the ninth episode of the fourth season of *Person of Interest*, the 77th episode overall. It was written by producer Erik Mountain and directed by Richard J. Lewis, and first aired on November 25, 2014, on CBS in the U.S. and CTV in Canada. The series follows a government computer system called the Machine, which predicts terrorist acts, and a team—John Reese, Harold Finch, and Sameen Shaw—who handle lower-priority "irrelevant" crimes. After the activation of a new program named Samaritan, the team’s safety is threatened. In this episode, the team receives Elias’s number and must protect him from a war with the Brotherhood. Shaw’s cover is blown, forcing her to hide from Samaritan. The title references the proverb "better the devil you know than the devil you don't."

According to Nielsen Media Research, the episode was seen by an estimated 9.04 million household viewers, with a 1.7/5 ratings share among adults 18–49. It received highly positive reviews, with critics praising Enrico Colantoni’s performance, the action scenes, and the setup for future episodes.

**Plot**

Shaw and Rousseau engage in a gunfight at a department store, but neither is injured. Shaw escapes with Root’s help and is taken to a moving truck. With her cover compromised, Root transports Shaw to a safe location, where Fusco picks them up. Reese is assigned to protect Elias after realizing he is the next number and spotting Brotherhood members following him. Reese reveals his mission to Elias, who remains calm. After a failed assassination attempt, Reese takes Elias and Scarface to another location. Elias seeks shelter with Gino, but they discover Gino is working with the Brotherhood, and suspect other allies have betrayed Elias. They search for Elias’s accountant, Bruce Moran, who may be his only trustworthy ally.

Rousseau finds leads on who picked up Shaw and poses as a DEA agent to question Fusco. With Finch listening in, Fusco doesn’t fall for it. Finch tells Shaw about Reese’s situation, and she decides to help, despite Root’s protests. Root agrees to assist but instead leads Shaw to a fake location and injects her with a sedative to protect her. Reese, Elias, and Scarface arrive at an empty building owned by Elias to retrieve money from a vault. The Brotherhood arrives, wounds Scarface, and takes him hostage while Reese and Elias hide in a secret room.