Pay close attention to the 2010 Iraq scenes, which clarify why Alex's brother was targeted and how Reese's "code" has evolved.
The Machine sends Root to work as a courier driver. She discovers Samaritan is using the courier service to spread malware via physical equipment. Person of Interest 5x3
The code the Machine sends to Finch translates to an Emily Dickinson poem , "Cocoon Above! Cocoon Below!", symbolizing transformation. "Person of Interest" Truth Be Told (TV Episode 2016) - IMDb Pay close attention to the 2010 Iraq scenes,
This episode is a deep dive into Reese's morality and the consequences of his actions as an operative. "Cocoon Above! Cocoon Below!"
Alex Duncan ( Stephen Plunkett ), a computer security expert.