Person of Interest's 100th episode flipped a switch in Harold Finch. With only three episodes left, Michael Emerson's billionaire software engineer will throw his moral code out the window.

Samaritan needs to be stopped; there's no two ways around it. The murderous AI has had Team Machine on their back foot all season, but, in the wake of Root's (Amy Acker) death, Finch will go on the offensive.

"We've long wanted to see what happens if Finch finally gets off the sidelines and says, 'F--- it,'" executive producer Jonathan Nolan told TV Insider. "We see a little bit of the guy that we've met in flashbacks, but haven't engaged with since. What happens when someone that smart and capable decides enough is enough? "

Finch has always tried to use his humanity to keep the Machine in check, ensureing that his squad doesn't go around killing every potential baddie in the country. As the series come to an end, the bespectacled recluse will have to revaluate his position.

"I think the impact of what happens in "The Day the World Went Away" is Finch has had this moral philosophy, and it's not that he abandons it-it's not like we're saying Finch's philosophy all these years was wrong, it's just that it's challenged," Nolan explained.

Look for the lead to eschew his partner with Reese (Jim Caviezel) as he goes lone wolf in "Synecdoche" and ".exe" (see a preview below).

The team must unravel a conspiracy and stay ahead of the Secret Service when the President of the United States becomes their newest POI. Also, Finch separates himself from the team and considers taking drastic action to combat Samaritan," CBS teased in regards to episode 11.

The following week, Reese and Shaw will race to catch up with Finch, as "he infiltrates a maximum-security government facility in a desperate mission which could mean the end for not only Samaritan, but for himself and The Machine as well."

Find out more when Person of Interest airs Mondays and Tuesdays at 10 p.m. ET on CBS.