Michael Mosley Talks The Sinner Season 4: "They've Really Created Quite a Magic Trick"

The last time we had the opportunity to chat with Michael Mosley, he was starring on the short-lived Fox series, Next.

This time around, he's landed on a bonafide hit with USA Network's well-received The Sinner, from executive producer Jessica Biel and starring Bill Pullman as frazzled detective Harry Ambrose.

The Sinner Season 4 finds Harry and his gal-pal Sonya (Jessica Hecht) visiting an island for a bit of rest and relaxation before Harry gets embroiled in a local mystery.

Michael plays Colin Muldoon, the uncle of a young woman on the island, Percy Muldoon (Alice Kremelberg), who gets under Harry's skin before she goes missing, sparking an island-wide search.

Of course, as Harry digs into her disappearance, the Muldoons, a prominent fishing family on the island, will come under scrutiny.

Other Muldoon family members include matriarch Meg (Frances Fisher) and Sean (Neal Huff), Colin's brother and Percy's father.

Interestingly, Michael first auditioned for a role on the show in conjunction with The Sinner Season 1.

He didn't get the part, and whether that disappointment was niggling at him when everyone else was watching and enjoying the first season (and second and third) or not, Michael chose not to watch. Still, nobody let him forget about it that easily.

"But ever since that show's been on, people will be like, 'The Sinner. The Sinner. Have you been watching The Sinner?' And I was like, 'No, I haven't.' There's so much content now. You can't see everything," Michael said.

When he discovered from his agent that he was gaining traction on a part in The Sinner Season 4, Michael thought he better check it out. With the role of Colin inching ever closer, Michael was finally mid-way through The Sinner Season 3.

Michael recalls calling his girlfriend in the middle of it. "I was just like, 'They just put Bill Pullman in a fucking grave. They just buried him.' And I was like, 'This thing's crazy.' And I just was kind of in love with it at that point. I was like, 'This thing is bananas cool.'"

He continued, "Bill [Pullman] and Derek [Simonds] have created this great, brooding, weird detective, that's so great in the pantheon of great -- Sherlock or Philip Marlowe, or these kinds of detectives that become part of the zeitgeist. I think he's just added such a great layer to that, with this Ambrose character he's created."

Michael said, "They've really created quite a magic trick with this show," as he raved about how they've stuck the landing every season with complex and twisty mysteries.

So, how does Michael fit in? He shared his thoughts on Colin from his perspective. "Colin is a lobster fisherman who lives on an island off the coast of Maine. He lives by himself, but he's in a tight tribe with his brother and his niece, and his mother.

"His dad was a lobster fisherman. His dad's dad was a lobster fisherman. This is what they do, and this is what they know. And they work hard and drink hard. But when we meet Colin in this show, he's in recovery, and he's no longer drinking. He's in AA.

"But he's kind of traded the bottle for the Bible. So there's a bit of a sanctimonious kind of pressure he puts on those around him, now that he's found the light."

Revealing that Colin has taken over the alpha role in the family in the wake of his father's death, Michael also believes Colin to be Meg's favorite soon.

Michael doesn't think he has much in common with his character.

"I'm not much like Colin, but as far as those hard-asses, 1,000-yard stare kind of guys, I think I grew up with guys like that. They all went off to work at John Deere and whatnot, and I went and put on makeup now for a living. So I'm a little different, as you can imagine. But I just kind of know that those guys -- few words, quick to anger, those kinds of guys."

Behind the scenes, Michael can't say enough about the experience as a part of the wonderful Season 4 cast. "I felt really lucky to walk out of the pandemic and onto this set. I felt enormously grateful that a show of this kind of pedigree, with this kind of cast.

"Frances Fisher is great. She will not stop talking about Titanic. That's all she wants to talk about. No, I'm just kidding. And Neal, Neal Huff, he's like, 'To Kill a Mockingbird, the most successful Broadway show of all time, yadda, yadda, yadda.' I'm like, 'Okay. We get it, Neal,'" Michael laughed.

"Everybody was so good and so much fun. Sometimes I've found when you're doing this heavier stuff, it's really important that when they call cut, and when everybody feels like they've done their job, and when everybody feels good, then it's good to kind of ... Everybody busts balls and lightens the mood, and we keep it light.

"We try to keep it light. That's what I've found. That's another good thing about this job that every new show you go on, you collect these people, these other freaks that went off and joined the circus like you did. It's fun. You just build your family in this business, and I feel like I've made a bunch of new family members on this show."

If you watch The Sinner online, you have tried to wrap your head around every season-long arc as it unfolds.

When asked if he thought viewers might catch on to the twists and turns of the fourth season mystery, Michael said, "I'm pretty confident people won't be able to guess until maybe seven or eight, towards the end.

"I don't think anyone's going to have any ideas of what's going on in the beginning. ... I think we've got some good twists in there. We'll give some people some proper emotional whiplash."

Any attempt to gain insight into whether Colin Muldoon is a good guy or a bad guy was brushed over with insightful generalities, which, given the mysterious nature of The Sinner, is good enough for us.

"A bad guy doesn't think he's bad. He's got a motive and an objective, just like anybody else. So I don't ever want to be twisting a mustache or anything unless I'm in a cartoon version, or unless I'm in something that you're supposed to do that. But when it comes to something that's based in reality, I don't ever really want people to know what I'm thinking."

Michael does suggest that Colin might be a little too self-righteous, using his religion to guide him. "When you have a book that can justify everything you do, and if you can apologize for the things that you do that are fucked up, you can get away with a lot of stuff that way."

It's always fun to get a concise take on someone's view of an upcoming show, and Michael's three words to describe The Sinner Season 4 are spinetingling. "God, forgive me," he said.

We have an interview coming with Alice, and Michael wondered what her answer was to the same question. "Everyone's a sinner" is what she said, to which Michael said, "Oh, that's good."

The realization that he and Alice were thinking similar thoughts made Michael recollect a conversation he had at the beginning of the production.

"I also asked Derek. When I first got there, I was like, 'Harry, he immerses himself in these cases too much, and he starts to become ... He becomes part of the blood and guts of the case and the people involved. And that's kind of his thing.

"But also, it seems like every season there seems to be some kind of existential peccadillo that he's wrestling with.' And I said, 'Well, what's ours? How do we serve as this character you guys have created? And what's happening this year?' And he said, 'Guilt.' He said, 'It's all about guilt.'"

Knowing the foundation of the season helped Michael become Colin. He likes knowing the direction of the story, even if he doesn't have the full picture of what will occur.

"Something like this that's serialized and boarded, and they know what they're doing, I appreciate that. I appreciate being let into the loop so that I can make plans for how to stick the landing at the end. Or try to, at least attempt to," Michael said.

After noting he's heard of directors who don't trust their cast with script copies in advance, Michael shares that he views TV and movie production as a team sport.

"I was in bands growing up as a kid. So I really think it's an egalitarian thing, and everybody gets together, and everybody plays an instrument, and there shouldn't be one person hovering over the whole thing, menacingly, pulling puppet strings. If you want to do that, just write a book."

His concern is that every kernel of knowledge that an actor gets about his role can affect how it's played. "It's a collaborative effort because if you don't understand your character, your emotions are going to betray that.

"And then if you get to something at the end, and you've been doing this whole thing this whole time, and then they're like, 'Oh, no. You're ex-military.' And it was like, 'Oh, I am? Oh, I'm ex-military now. Okay.' Well, that would've changed how I stood or sat or how I would grab my fork."

The Sinner experience didn't leave anyone in the dark about how they should carry their character through the production. "So I was very pleased to have a rough sketch, rough blueprints of what the entirety of the season was going to be. I thought it was really good, and it showed that he trusted us."

Since The Sinner has rotating series regulars depending on the season-long arc, Michael is already working on his next project, starring in the Hulu original series, The Girl from Plainview. You may not be familiar with the title, but the story has been kicking up dust for years now.

It follows the true story of Michelle Carter, who was accused of encouraging her online boyfriend, Conrad Roy, to commit suicide.

"She ended up actually being convicted of involuntary manslaughter and served a year and change, which, it's kind of weird, because yeah, that was shitty to do, but is texting someone to do that a crime? It's an interesting precedent that they were setting with regards to that.

"And also, these iPhones, we're all kind of guinea pigs with these things right now. It's just an interesting dialogue about whether or not this 17-year-old girl and this 17- or 18-year-old boy lived in this fantasy in their texts. I don't know. Can you text someone to do that, and is that a crime if they do it? Is that your fault? It's an interesting story."

We agreed that it's opening a whole different avenue of abuse and blame that we've never experienced before. Michael will be playing Michelle's attorney, so he'll be working alongside Elle Fanning as Michelle.

I made a promise to contact him again when The Girl from Plainview is closer to air because that's going to be one we cannot miss.

For now, you've got Michael's performance as Colin Muldoon to look forward to, as The Sinner's latest season premieres Wednesday, October 13 at 10/9c on USA Network.

We'll be watching. Will you?

Carissa Pavlica is the managing editor and a staff writer and critic for TV Fanatic. She's a member of the Critic's Choice Association, enjoys mentoring writers, conversing with cats, and passionately discussing the nuances of television and film with anyone who will listen. Follow her on X and email her here at TV Fanatic.