Justin Timberlake
Best known as one of the world's most successful singer-songwriters, Tennessee-born Justin Timberlake has a lengthy list of credits as an actor, including Trolls, Shrek the Third, The Love Guru, and Yogi Bear. Timberlake's role in The Social Network as Napster founder Sean Parker came at a point in Timberlake's career when he was focusing more on acting work than music.
Andrew Garfield
Though Andrew Garfield’s first big acting break came from his role as Tommy in the 2010 movie Never Let Me Go, he is perhaps best-known for playing the role of Peter Parker in the 2012 Amazing Spider-man franchise. He has since gone on to perform in Broadway productions, receiving a Tony Award in 2018 for his role as Prior Walter in a production of Angels in America.
Jesse Eisenberg
Praised for being one of the most talented young actors in Hollywood, New York-born Jesse Eisenberg made his screen debut in the series Get Real in 1999. Though he played many roles in the following decade, it wasn't until his starring roles in 2009's Adventureland and Zombieland that he gained widespread recognition as an actor. The following year, Eisenberg's role as Mark Zuckerberg led to nominations for a BAFTA, a Golden Globe, and an Academy Award for Best Actor. Eisenberg has said in interviews that he would play Zuckerberg again if a sequel to The Social Network were made.
Armie Hammer
Although his first leading role was in the 2008 film Billy: The Early Years, American actor Armie Hammer earned widespread recognition for his role as Cameron and Tyler Winklevoss in The Social Network. On set, Hammer played only one of the twins while the other was played by Josh Pence. Director David Fincher later superimposed Hammer's face onto Pence's body so it appeared as though Hammer was playing both roles.