The Person of Interest team will have to keep a watchful eye on one of their own this season. Shaw is back, but will she be the same old operative Root knows and loves?

As for as Finch (Michael Finch) and Resse (Jim Caviezel) are concerned, Shaw's (Sarah Shahi) extended stay with the Samaritans makes her a liability. When she returns in "6,741," her odd behavior will have everyone on guard.

"Shaw escapes her captors, but the team is unsure of her mental state when she begins to act paranoid and reckless," CBS said of episode 4.

"[They're] trying to sort out where Shaw's head is at," executive producer Greg Plageman told TV Insider. "Whether or not she's been brainwashed or reprogrammed in some way. And where her allegiance now lies...Shaw was always damaged in her own endearing sociopathic way, but she was our sociopath. Now it's not so clear."

Whatever is going on with Shaw, it will resolve in time for Root (Amy Acker) and her girlfriend to hit a few important milestones before the finale season comes to an end.

"I think you'll see a lot of milestones," executive producer Denis Thé told TV Line. "As a writer, these ladies are so fun to write - they're flirty, they're fun - but there's a deeper relationship, a deeper emotion simmering there."

Person of Interest will return to CBS on May 3. After a yearlong hiatus, fans will finally learn the fate of the Machine in "B.S.O.D."

"Reese and Finch attempt to rescue the Machine's source code before it deteriorates beyond repair," CBS teased. "Also, Root fights for her life against an onslaught of Samaritan's agents and Fusco is faced with hard questions following the deaths of Dominic and Elias."

Person of Interest will air Mondays and Tuesdays at 10 p.m. ET on CBS. Click the video below to see a preview for the premiere.