The series revolves around a computer program for the federal government known as "The Machine" that is capable of collating all sources of information to predict terrorist acts and to identify people planning them.
Shaw (Sarah Shahi) sedates her nurse and uses a tank to escape through the walls of the hospital while Jeremy Lambert (Julian Ovenden) alerts the operatives to find her.
Having abandoned the team, Fusco (Kevin Chapman) asks Elias (Enrico Colantoni) for help in investigating the events at the tunnel.
Bear attacks the man and Root arrives with more anti-virals found by the Machine, saving everyone including Fusco.
Blackwell and his handler, Mona, discuss the quelled epidemic and declare it a success: the CDC is requiring everyone to be vaccinated, which will result in Samaritan learning everyone's DNA.
Shaw responds by killing him and escaping on Lambert's vehicle to flee the prison while hearing radio reports about the events on New York.
In its original American broadcast, "Reassortment" was seen by an estimated 4.92 million household viewers and gained a 0.9/3 ratings share among adults aged 18–49, according to Nielsen Media Research.
Matt Fowler of IGN gave the episode a "great" 8.6 out of 10 rating and wrote in his verdict, "In 'Reassortment,' Jeff Blackwell discovered the reason he was chosen by his new employers and embarked on a mission that led him down an even darker path.
Club gave the episode an "A−" grade and wrote, "'Reassortment' pairs an A-plot about a deadly viral outbreak with a B-plot that involves Shaw breaking out of prison.