A lethal government operative who tracks and stops terrorist threats before they occur finds herself on the run – and the new focus of Reese and Finch's attention. However, their pursuit proves to be their most formidable when they discover that her remarkable skill set equals their own.
Daniel Aquino is introduced in the flashback to his demise. This event causes members of Catalyst Indigo to question the source of their intelligence from "Research".
Control is mentioned as part of the leadership of ISA.
After the events of this episode Sameen Shaw is presumed dead.
This episode introduces viewers to the ISA section responsible for processing the "Relevant" list, who are marked with blue squares (or indigo) by the Machine. Like Finch, the ISA agents receive Social Security numbers, but of people suspected of being a threat to the security of the United States.
There are many more red squares visible in the surveillance feeds, along with more symptoms of the embedded code from “Dead Reckoning”.
Unlike other episodes, the title sequence is cut off seconds after beginning, leading us into the world of the "relevant numbers". This was the first time this has occurred.
Aconitine, or monkshood, is a poison usually extracted from an Asian plant called aconite. It has historically been difficult to detect in cases of poisonings, especially 12 hours after its injection.
Atropine is considered an essential drug by the World Health Organization, primarily used to counteract cardiovascular effects such as those caused by aconitine.
Fentanyl is a commonly prescribed yet often-abused anesthetic and pain killer that is 100 times more powerful than morphine. A derivative of Fentanyl, combined with other gaseous compounds, was used to pacify Chechen extremists during the Moscow Theater Crisis in 2002 . Cole's remarks in East Berlin about the gas may have been a reference to that use.
Flashbang grenades are not intended to cause physical harm, however if one goes off nearby, it can cause temporary blindness, disorientation and hearing loss.
A "dirty bomb", otherwise known as a "Radiological Dispersion Device" (RDD) is composed of a conventional explosive which is used to spread radioactive substance(s) over a wide area.
To celebrate Person of Interest airing on Netflix starting September 1, 2015, IGN.com asked Jonathan Nolan and Greg Plageman to pick a few of their favorite episodes. Nolan picked "Relevance" as one of his favorite episodes as it was a "super cool" experience to direct it, including the introduction of Sarah Shahi as Sameen Shaw. Plageman picked it as one of his favorites because although he loves “Pilot”, this episode fulfilled a lot of the things they wanted to do in the pilot. He also liked it because although it wasn't focused on the main characters, it was still a riveting episode, and captivated their audience, showing that Person of Interest could do anything.
Reese first spots Shaw at the 33rd Street station on the 7 subway line.
Bloopers and Continuity Errors
Berlin police uniform patches depict a bear (the coat of arms of Berlin), not a cross.
The format of the German license plates shown in Berlin is wrong. It should be XX-XX-123
In the scene where Shaw is encounters two of Bekhti's henchmen she's been following, there is a sign at the door with 'Exit' instead of 'Ausgang'.
As Shaw breaks in at the Berlin apartment, she does so by removing the lock cylinder from the door. We can see her throw it away. In the next scene, when she opens the door, the lock is still intact. Furthermore, when she enters the apartment, the man in the kitchen is seen on the ground, his hands in front of his head and the carton of orange juice at fairly the same level. But in the next scene, his hands and the carton lie in front of him. As she walks to the first man who succumbed to the gas, his rifle was lying next to him, his left leg leaning against the pillar. But when Sam moves the rifle away with her boot, we don't see the man anywhere. Later, in Cole's surveillance images, as Cole and Shaw are looking for #3 (man in the kitchen), we see #1 in the original position but his legs have moved.
When Shaw regains consciousness, the large sweat stain on her shirt disappears for one shot, before reappearing.
Shaw arranges to meet in "Manhattan at the Suffolk Hotel, room 1458, 5:00 PM tomorrow." Apparently she arrives at the 37th floor, not the 14th floor.
At the cemetery, when Bear licks Shaw's face, we see Bear run away towards a building, but we see no one standing there. Later, we see Finch and Reese standing in front of that building, but they weren't present in the previous shot.
"Future Starts Slow" by The Kills - When Shaw walks away/end of episode. The song's lyrics are censored to protect underage audience. When Shaw throws the gun to the garbage it's heard: "You can holler, you can wail, you can swing, you can flail, you can fuck like a broken sail". The word fuck is deleted from the soundtrack.
The phone number (917) 285-7362 written on a card that Finch gave to Shaw at the end of the episode is an actual telephone number that leads to Harold Wren's voice mail. This telephone number is currently in service and appears to be a wireless telephone number from the NY City area on the Verizon network.
The same phone number previously appeared in “Firewall”. Carter sent escape instructions to that number, which belonged to Reese's phone.
When someone goes to the trouble of collecting spent shell casings to avoid detection, it is referred to in the armed services as "policing their brass"