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201The Contingency” (Finch) 209C.O.D. 217Proteus
202Bad Code” (Root) 210Shadow Box 218All In
203Masquerade 2112πR 219Trojan Horse
204Triggerman 212Prisoner's Dilemma” (Reese) 220In Extremis” (Fusco)
205Bury the Lede 213Dead Reckoning” (Stanton) 221Zero Day” (Finch/Ingram)
206The High Road” (Finch) 214One Percent” (Finch/Ingram) 222God Mode” (Finch/Hersh)
207Critical 215Booked Solid
208Til Death” (Finch) 216Relevance
In Extremis

POI 0220 Main.png



Air dateApril 25, 2013

Running time43:47

Production code2J7220

Written byGreg Plageman
Tony Camerino

Directed byChris Fisher


ID(s) from IntroID.220/2562.14

Images (50)

That storm on the horizon that I mentioned? I'm afraid it's arrived.

— Finch

"In Extremis" is the 20th episode of season 2, and the 43rd produced hour of Person of Interest. It originally aired on April 25, 2013.


When a luminary in the world of medicine is poisoned, Reese and Finch have just 24 hours to determine the deadly toxin he was given and find the person behind the attack. Meanwhile, Detective Fusco's past corruption catches up with him when an informant gives the Internal Affairs Bureau the crucial information they need to send him to prison.

Origin of the Title

In extremis is a Latin phrase, which refers to extreme conditions or at the point of death.

Main Plot Points

  • Reese goes undercover as a server while Dr. Richard Nelson is honored as Professor Emeritus. Someone gives the doctor Polonium giving him radiation poisoning so he has only one day to live.
  • The doctor reveals that he unintentionally revealed a secret regarding the impending failure of a drug trial to Brandon Boyd who engaged in insider trading based on the information.
  • With help from Louis Azarello, HR attempts to frame Fusco for the murder of James Stills.
  • Fusco reveals the truth of his past to a horrified Carter.
  • Carter removes Stills' body with Bear's help, saving Fusco. Azarello later recants due to Elias ending the investigation into Fusco completely.
  • The Machine, after growing increasingly erratic, shuts down its primary systems due to the virus.


In a 2004 flashback, it is shown how Stills gets Fusco involved in HR.

Episode Notes

  • At the beginning of the episode, Dr. Nelson is being awarded Emeritus status. In academia, an emeritus professor is one who has retired with merit, that is, with a substantial body of work. The title is an honorific accorded by colleagues rather than academic standing. The show appears to be portraying the status as being awarded to Nelson before retirement, which would be erroneous.
  • Dr. Nelson was poisoned with polonium, a radioactive element. Similar to uranium, it is also highly toxic, and can kill through exposure or ingestion.
  • The Domain Awareness System used by IAB to find the disturbed ground was developed by the New York Police Department in collaboration with Microsoft. Its objective is to harness and analyze video feeds, license plate reader output and other data sources as part of an on-going anti-terrorism initiative. This system has several eerily similar attributes of the Machine, as detailed in an episode of the PBS documentary series Nova detailing the capture of the Boston Marathon bombers.

Quotes from Plato

Plato was Greek a fourth century BC philosopher and mathematician. Along with Socrates and Aristotle, he laid the foundations of western philosophy and scientific thought. The episode juxtaposes two of his quotes, one literally and one ironically:

  • "Knowledge is the food of the soul." (Plato, quoted by Dr. Nelson)
  • "He who commits injustice is ever made more wretched than he who suffers it." (Plato, quoted by Alonzo Quinn)

The episode uses juxtaposition, the act of placing or positioning abstract elements side-by-side or back-to-back to illustrate a contrast or contradiction, by transitioning from the scene showing, the respected but flawed, Dr. Nelson being honored to the scene of Cal Beecher's funeral. To create a sense of irony, the two characters recited quotations from the Greek philosopher Plato, which define their characters while bridging the two scenes, setting up the contrast between the good, but dying doctor and the bad but living Alonzo Quinn, who set in motion the chain of events that led to the demise of his godson. Drama frequently uses these two elements to underlie the emotional content of stories.

Production Notes

Bloopers and Continuity Errors

  • When Dr. Nelson is finishing up the conversation with his daughter, Reese is bringing his medical bag up to him and carrying it with his hand underneath the bag. When it goes to the view of the machine he has it by the handles.
  • Reese killed Detective Stills and asked Fusco to bury him in September as the pilot showed, but in this episode's flashback we can see snow on the ground, suggesting that Fusco buried Stills in winter instead of in fall.


  • The person of interest is a dying man trying to solve his own murder. This plot line is a variation on a theme from the 1950's film D.O.A. In that film, the protagonist was poisoned with a luminous toxin (most likely radioactive).
  • Coincidentally, Dennis Boutsikaris, who plays this week's person of interest, recently played a character in similar circumstances on CBS's Elementary, in the episode "Possibility Two". Elementary, a contemporary reimagination of Sherlock Holmes, was broadcast immediately following Person of Interest and also is set and filmed in New York.
  • In 2006, Alexander Litvinenko, a former Russian intelligence operative, died in a manner similar to Dr. Nelson when he unknowingly ingested a lethal dose of polonium-210.
  • According to Business Insider, the fictional hedge fund in this episode, VAC Capital, bears some similarity to a company based in Stamford, Connecticut, called SAC Capital, which was under investigation for insider trading of certain pharmaceutical companies at the point of time this episode was produced. SAC pleaded guilty in November 2013, and is part of Point72 Asset Management since 2016.


  • "Domain awareness, my friend. Satellites, they're changing the world. You pick a time and place, we send you a photo of the ass hairs on a frog, or in this case, disturbed plots of earth in Oyster Bay." (Det. Soriano, Internal Affairs Bureau to Fusco)
  • "There are people who want to see you go down, and people who don't give a crap about you. And Fusco, I don't think anyone gives a crap about you." (Det. Soriano to Fusco)
  • "If you will excuse me, I got a date with a sock" (Azarello)