who is the hacker in person of interest
List of Person of Interest characters Root (played by Amy Acker), born Samantha "Sam" Groves, is a highly intelligent computer hacker and contract killer, obsessed with Finch and the Machine. Aside from her extraordinary intelligence, she has also displayed an uncanny ability in the use of firearms, a very high threshold for pain (S2 Ep2, "Bad Code", where she gets physically assaulted by Denton Weeks; S3 Ep12, "Aletheia", where she is severely tortured but not broken by Control) and a proficiency for social engineering (she has successfully posed as a high-end psychiatrist (S1 Ep23, "Firewall"), an assistant to the United States Special Counsel (S2 Ep15, "Booked Solid") and as a legitimate FBI agent (showing up in Lionel Fusco's New York City Police Department 8th Precinct with a legitimate warrant and an FBI badge, S3 Ep17, "Root Path").