Most of us have a painful childhood memory we long to forget. Not Malcolm Bright (Tom Payne).

The unhinged, heavily medicated and surprisingly endearing criminal psychologist of Fox’s breakout Prodigal Son has a block of missing time he’ll do anything to remember: What happened in the days (weeks? months, even?) before young Malcolm called the cops on his dad, serial killer Dr. Martin Whitly (Michael Sheen)? And where is “the girl in the box,” a body Malcolm saw in their home but police never found?

“It’s brave and makes for some great television,” Payne says of Malcolm’s ongoing struggle to piece together repressed memories, which have been surfacing more frequently since he started consulting with the NYPD and renewed contact with Martin. The network agrees: Fox has ordered a full season of the twisty drama.

Payne chatted with TV Insider about that vote of confidence, tonight’s Halloween episode, and whether shippers should get their hopes up.

First question: Did you have time to do anything on set to celebrate the pickup, or was it business as usual?

Tom Payne: Honestly, I was kind of in shock. We were filming by Astor Place in the middle of New York, in rush hour, so it was crazy busy. The showrunners texted me: “Good news coming.” And then a few minutes later, “Nine more [episodes].” I literally texted them back, “What?” It mainly was just the fact that it flips my life upside down: I thought I lived in Los Angeles, but I guess I live in New York now. Obviously, it’s amazing. It means that we get to concentrate on telling the story. And it’s great for the audience as well, because they know that they’ve got a lot more to come.

At the end of last week’s episode, Malcolm recovered an old father-son photo — the two of them with a car he’d been seeing flashes of, perhaps with the body of “the girl in the box” inside. He’ll be trying to get to the bottom of that photo now. Did you know “the girl in the box” would be an ongoing mystery when you signed on to the show?

I didn’t. When we did the pilot, I didn’t think that was something they were going to continue with. But when they brought it up and said, “Oh, we’re going to carry on that mystery,” I loved the idea. The whole storyline of his father putting doubts into Malcolm about what [Malcolm] might have been involved in, and who was “the girl in the box” — why does no one else remember her or believe Malcolm? Maybe it was a dream, maybe it wasn’t a dream. I think it’s fantastic. And we’re all waiting for the next scripts to see what the next turn in that story is. So we have the case-of-the-week, but then as the show goes on, these other storylines build, and everything starts to coalesce.

It’s clear the case-of-the-week always relates back to Malcolm’s story somehow. How so in tonight’s episode?

There is a small child involved, and the murder surrounds his family. So Malcolm sees some parallels, and the case is quite personal to him. He immediately becomes protective of the child, and that might affect how he approaches the case and how he lives with the case.

We’ve seen how Malcolm’s childhood trauma continues to impact him. What’s been the most challenging part of portraying that, and is hurling himself out a window during a night terror the most extreme thing we’ll see?

Well, the window was pretty fun. Physically, so far, that’s the most extreme thing. The end of Episode 4 was pretty emotional, when Malcolm watches the video [of his mother’s interview the night his father was arrested]. I hadn’t really prepped myself for how I was going to react to the video, and I just burst into tears every single time. It was cathartic, actually. There’s a great moment in there when she says, “I knew” and he thinks, “Oh, my God, she did know [about the murders].” And then when he sees that she meant [she knew something was off, but she thought Martin was cheating on her], that gives a great amount of relief for him. Malcolm is just on the edge most of the time, and it was nice to find the center of that relationship [with his mother] in this episode.

But going there — I have been going there in every episode with him, and it’s really draining. All of the scenes with Michael Sheen are just really exhausting, because there’s so much emotion going on under the surface — like, “I hate you but…” and “Where’s my dad?” I have to really look after myself physically. Even having a drink at the weekend… [Recently], I was like, “Oh, I don’t work tomorrow, and we’ve got our wedding planners in town, let’s go have some drinks.” Not that I got completely wasted or anything, but [the next morning] I’m like, “I just can’t do it.” It takes too much out of your body. I just have to live this life of a monk for the time that I’m shooting, because it is a lot. But I love my job. This is the best part I’ve ever played.

There is this sense of childlike giddiness at times in Malcolm, which is fun to watch. Like the first time we saw him with the psychologist he’s been seeing since he was a boy — sitting in the chair like a little kid, taking a handful of lollipops when he left. But it also makes you wonder how his PTSD might have stunted his emotional growth.

I think any trauma stunts something within you, and you close the door to some things. He left New York and went to join the FBI. He ran away from everything. Coming back to New York, meeting up with his family, has cracked that door a bit. But he’s a lot of different things all at once. He’s not a very stable human being. [Laughs] But he’s trying to approach that rather than just close it off still. So that means that, yeah, he’s going to be a bit all over the place for a while. We all need to take a look at ourselves, and examine the parts of ourselves that are not quite working and understand why.

Malcolm’s sister, TV journalist Ainsley (Halston Sage), is determined to interview their father. We know their mother, Jessica (Bellamy Young), is going to be hell-bent against that happening. How will Malcolm handle the idea?

Malcolm’s been trying to shield her from Martin their whole life — and shield her from the fallout. Obviously, Ainsley knows what the general public knows about her dad and everything that happened, but she doesn’t really know him. She doesn’t really remember him that strongly as a father because she wasn’t old enough. So for Malcolm, there’s just a huge fear that her naïveté will get her into trouble with her dad. He’s terrified of that, as is Jessica. But Ainsley is so headstrong, she’s going to do what she wants to do. She’s going to do that with a very, very clever man if she gets to do it, and we’ll see where that goes.

To end on a lighter note, the show finds moments of levity with Malcolm’s relationships with his new cop colleagues, particularly detective Dani (Aurora Perrineau), who we’ve seen him bond with multiple times as they learn more about each other’s backstories of being saved by boss Gil (Lou Diamond Phillips). Do you like that some fans are already shipping them?

I like all that fan involvement. I had it on The Walking Dead as well, and it’s fun. I don’t think he should get into a relationship anytime soon. [Laughs] I’m not sure he’d be great boyfriend material right now, and I’m not sure that he would advise that for himself either. That whole relationship with Dani, and also with Frank Harts’ character, JT — it’s just fun for him to bump up against them.

And then also [medical examiner] Edrisa and her infatuation. Keiko [Agena] is just hysterical. We were shooting a scene the other day, and my fiancée came to the stage, and she was just like, “Oh, my god. Keiko.” Every page, she’s doing it differently. She’s just got this way of hitting, with pinpoint accuracy, many different ways of approaching a line.

Those different characters bring out different sides of Malcolm as well. Anyone who shows Malcolm a bit of care and attention will get something out of it at the end of the day. But not necessarily romantic. He needs a hug, basically. [Laughs] He’s not getting one from his mom. That’s actually the most amazing part of Episode 4 — all this emotional stuff happens, and then they have the scene at the end, Malcolm and Jessica, and she pats him on the shoulder and walks away. They can’t hug each other! They’re so reserved emotionally. Their relationship is so interesting like that.

I was going to ask you about Edrisa, because it’s clear she’s smitten with Malcolm and he knows it. He gives her a sweet smile whenever she’s bumbling around him. What do you think Malcolm makes of her?

She’s incredibly endearing. They’re geeks about the murder stuff, so they have that connection. I’m not sure if anything would ever happen there, but it’s nice for him to be able to talk about certain things with her that he can’t talk about with other people — the details of the bodies that they’re dissecting.

Prodigal Son, Mondays, 9/8c Fox

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