Person of Interest's Carrie Preston on True Blood

Credit: John P. Filo/CBS[/caption]

[SPOILER ALERT! If you haven’t watched this week’s episode of Person of Interest, stop reading now, or else we will enter your social security number into the Machine…]

Another week, another big reveal on Person of Interest. At the end of this week’s episode, “No Good Deed,” Reese (Jim Caviezel) traced Finch (Michael Emerson) back to what he thought was Finch’s home address. But when Reese got there, Finch’s fiancée opened the door. (Dun-dun-DUN!) Yes, Finch used to be engaged, but his girlfriend thinks he died a few years ago in an accident. That means Reese isn’t the only one who lost a relationship because of his job.

But for longtime fans of Michael Emerson, the best surprise was that Carrie Preston, who’s married to Emerson in real life, played his fiancée. (You might know Preston as Arlene Fowler on True Blood or Elsbeth Tascione on The Good Wife.)

The couple first met 17 years ago, during a production of Hamlet at the Alabama Shakespeare Festival, and they’ve been anxious to work together ever since, they recently told EW. Preston even joined Emerson on Lost. “I thought it would be really special for me to play a character who was connected to his character,” Preston remembers. “Then I ended up playing his mother!”

For Person of Interest, she was excited to play someone who provides insight into Finch’s very private life. “He clearly sacrificed his own heart in order to protect her, which is very tragic and also extremely romantic,” she says. “We certainly have more empathy for him now.”

Preston doesn’t believe that her character knows about the Machine. But now that Reese knows she exists, he might prod her for more background on his mysterious partner. Or maybe Reese will act as a go-between for Finch. “It would be interesting to revisit this idea that Finch has an app on his phone that keeps him from ever getting within 100 meters of her,” says Preston. “He could get Reese to say things to her, because he can’t come near her himself.”

Next week’s finale will shed even more light on Finch’s background. When the Machine spits out the number of Dr. Turing (Amy Acker), a psychologist with a high-powered client list, Reese and Finch must protect her and the secrets she’s keeping. “This is somebody who helps explain some things about Finch,” Emerson recently told EW. “You’ll see her again next season.” Emerson also promises that there will be a big, cliffhanger ending. “All the powers have aligned against Reese and Finch. Surprising, terrible things happen.”

Preston won’t appear in the finale, though it’s likely that she’ll return next season. Says creator/executive producer Jonathan Nolan, “We would be thrilled to have Carrie back.” In the meantime, she’s gearing up for the next season of True Blood. What can she tell us about the new episodes? “We have not seen the last of Scott Foley’s character, Patrick,” she says. “We’re very much going to face some things from Terry’s past, and he’s a big part of that.”

Read more:

‘Person of Interest’ premiere review

‘Person of Interest’: See Astro on the series

‘True Blood’: 20 new photos from season 5