Firewall (Person of Interest)

The first season of Person of Interest closes with "Firewall," the 23rd episode, which aired on May 17, 2012, on CBS in the U.S. and CTV in Canada. Greg Plageman and Jonathan Nolan wrote it, with Richard J. Lewis directing.

Plot

The plot begins with Finch contacting Carter for help with Reese, but she is occupied with Agent Donnelly, who has located Reese escorting a woman on surveillance. A day earlier, Reese and Finch got a new number: Caroline Turing, a psychologist. Posing as a patient, Reese watches her. Meanwhile, Fusco meets with HR, represented by councilman Larsson and Officer Simmons, who have taken a murder-for-hire contract.

An anonymous client wants Turing dead, and Fusco must obstruct any NYPD inquiry. Reese, with intel from Zoe Morgan, saves Turing from attackers and hides her in a hotel. His face is caught on camera, prompting an FBI strike team. With Carter’s help, Reese and Turing evade both the FBI and HR members surrounding the hotel.

While Finch hacks systems, Root (posing as Caroline Turing) breaks into the Library. Finch learns the threat was blackmailed by an unknown benefactor. Reese gets Turing to Finch via a water plant, then holds off HR. Carter and Fusco join a chase, and Reese uses a grenade to disable an HR vehicle.

Finch waits with Turing in his car, but Corwin confronts him, demanding he shut down the Machine. Turing shoots Corwin dead. Finch discovers Turing’s records being deleted, revealing she is actually Root, who hired HR to stage her own murder—making Finch the real target. Reese arrives to find Corwin’s body.

Fusco sends HR evidence to the NYPD, leading to an arrest. Reese speaks to a surveillance camera, asking the Machine to help find Finch, and a nearby payphone rings.

Writing

Co-writer Greg Plageman called the scene where Root psychoanalyzes Reese the hardest he ever wrote, noting both characters lie about their identities while probing each other, and Root’s accuracy about Reese is unsettling, especially in hindsight.

Viewers

The episode drew 13.47 million viewers and a 2.5/7 rating among adults 18–49, a 4% increase from the prior episode. It was CBS’s most-watched show that night, beating The Mentalist and Rules of Engagement, but ranked fourth in its timeslot for 18–49, behind Grey’s Anatomy, a Big Bang Theory rerun, and American Idol.

Reviews were mostly positive.