David Costabile, who plays David on this week's episode of Soulmates, talks about how lost his character is, why he decides to pursue a relationship with Alison, and how the show's grounded-yet-futuristic setting impacts the story.

Q: Have you ever worked on a project set in the future? What was it like playing in that space?

A: I don't think I've ever worked on something set in the future. I think this is my first future thing!

I think in terms of production and style, we stay really grounded in how we know people to live their lives now. As an audience member [watching shows set in the future], there are times when you kind of squint and think, "What? How's that? That doesn't make any sense to me." But for Soulmates you're like, "The phones and the computers are different, but sure, 15 years ago the stuff that was in our hands looked nothing like what we have now."

The future setting doesn't distract you from the driver of the story, the psychology, and the thriller aspect—certainly not in our episode. The premise of this test that now exists seems plausible enough that you're willing to go with it. It's not a particularly large leap.

Q: What excited you about this script or the overall project?

A: Like most things that are intriguing to me, it's really about good writing. I felt like if I was able to do justice to the character and what they had written, you wouldn't really know exactly where he stood. You could have a compassionate response to him, even as you watch a lost soul get his soul crushed in front of you. That was intriguing to me. I thought, can I do it? Can I try to really walk that line? Can I be internally unbalanced enough to authentically create this character and sustain it so that the audience will actually give a damn to watch the whole thing through? I wanted enough likability—enough freedom and joy that this person has—but also see him slowly crushed under the weight of the decisions he's made. So that was what really drew me to the character and drew me to the possibility of playing him.

Q: David took the test before he was married, but left it private. What did you infer from that detail about your character?

A: He really struck me as somebody who is seeking something. On some level, he's a lost soul, right? He thinks, here will be the answer. When something that he left in the past presents itself and says, "When you were younger, you missed this. This is the opportunity for you. I'm here to tell you that you didn't open a door back then and here's the door and you can open it." He opens it and walks through it, and it's a terrible idea. I think he feels confident in his present self and thinks, "I got this, and I got the next thing, and then I'm going to get tenure. I'm doing it. I'm building this life. I'm building it the right way." And I think this memory is the trigger that trips him.

Q: How did you interpret David's interaction with the young student smoking in his office? Is it innocent?

A: I think that that's also part of the set-up. The writers are trying to set you up so when the information from his past comes to light, there's believability about him choosing to do it or not to do it. To me, it's much more interesting if from his perspective, it is in fact innocent. Trying to make the audience feel that imbalance, to feel like what the hell's going on?! This seems creepy... and is it creepy? I think that there's a verity about that in terms of students and professors. He obviously has experience taking the next two steps that one should never take with their student.

I think too hopefully at the very end—this is a very tricky end and was very challenging to get to, and I will leave it to the audience to say whether it is successful enough—the idea that, when he actually talks about Chloe and he says, "I loved her," is that he really did love her and that her suicide must have been extremely painful to him.

Q: His father-in-law is his boss. How does that impact his relationship with his wife and his work?

A: I mean it just doesn't seem good. He's an academic—and from my own experience of teaching at a university [at New York University] and also having friends who have done it and are lifelong professors—it's a very political and difficult world to live in. I think the things that you sacrifice in order to maintain your position are vast, and I think that he has given up a lot in order to basically just eat this guy's sh*t over and over. He can't get out from under him and it all sort of leads back to this feeling of instability inside of him. It's not really a surprise when [his father-in-law] says, "I don't like you. The only reason I'm doing it is for my daughter." And I think he knows that's true. He can't do anything about it and he feels quite helpless. I think it's demoralizing and infantilizing.

Q: It’s obvious that David and Alison feel something when they hug. Is this what he was afraid of?

A: I actually don't know if he had fear. To me, the reason that it spurs him to such an extreme action is that it's almost like a remembrance of things past, right? He has this particular bite of the madeleine and it opens something in him that either he had shut or he had never known was there. And it's the same thing that he did in the past—he's going to shut this down, seal this door off. But somebody says, "No, this door opens, opens and shuts, and you can walk through and it's a vast unknown world, dude. Go through it." And I think that the combination of Alison, and the memory of the moment when he took that test in his younger life is really powerful. When the opportunity is presented to him again, he can't not walk through that door.

They talk about the pull in the show, and I feel like I don't even know if he feels the pull towards her. I think he just feels this pull. I think that pull happens to him, and he's like, "Yes, yes, it does exist." I think he then may assign it to her because he feels it and is like, "Oh, it must be this person who just hugged and kissed me." But I think that is the seduction of that moment for him. He is seduced by the pull.

Q: What does it say about David that when he finds out Alison’s real reasons for being in his life that he responds with anger and threats, rather than compassion and understanding?

A: It's not pretty, that's for sure. The guy is somebody who's lost, and who thinks he's going to find surety in the acquisition of status, relationships, professional solidity, and financial security. He's really adrift, and has lost his way. When he's presented with somebody saying, "I'm going to take all of this away from you," he will fight for it. He's not going to give up that thing that even he almost recognizes is not the answer, but his reaction is that he's being mortally threatened, so he responds in a very aggressive manner.

Q: It's as though what’s happening to David and Alison is out of their control. Is there an element of that for David?

A: For the audience, you always want to give the option that it couldn't happen, right? If you just think, yeah they'll sleep together, he's going to ruin his life, then you're like, "Who cares?" But if the possibility is real that he's going to just throw the piece of paper away—you want to see that pull, the stretching of him until he breaks and then just makes a crap decision. Inside of that, the equal power of saying 'no' has to be just as strong as the saying 'yes.'

Read a Q&A with Sarah Snook, who plays Nikki.

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