Scott Speedman on What Surprised Him the Most About 'You' Season 3 (Exclusive)

The actor breaks down that open-ended finale and what the future holds for his character.

Spoiler alert! Do not proceed if you have not finished season 3 of Netflix's You.

Scott Speedman had revenge on the brain for much of You season 3, playing Matthew, a wealthy tech CEO who becomes consumed with Joe Goldberg after the untimely (and sudden) death of his wife, Natalie (Michaela McManus), in the first episode. For the Felicity alum, playing a character who begins to have a mental breakdown as he gets deeper and deeper into Joe's orbit was intriguing and exhilarating.

"He was mysterious to a point where you don't really know what he is. He has charisma, which was interesting. He's clearly a damaged guy, which was interesting. He's clearly trying to figure out something. There was a really interesting arc with him, where he started in a certain place because of certain circumstances and [ended] in a completely other place," Speedman told ET. "That was interesting to me, as opposed to something that just kind of flatlines along. He had a full transition in a way. That was really cool for me because I knew where he was going. He started as this cold, removed guy and not connected at all. That was interesting to see if I could pull that off."

But ask the 46-year-old actor, who's now appearing on Grey's Anatomy as a new love interest for Meredith Grey, about what surprised him the most about the current season of You and the answer is somewhat unexpected.

"The most surprising thing about Matthew's journey this season was the reconciliation with his son [Theo]. That was kind of interesting. I didn't see that coming," Speedman began, before stopping a beat and acknowledging the biggest stunner on a show that involves a lot of death. "And just that I survive."

Though Speedman said he was aware of the direction his character's arc would take (and that he'd survive it), it seemed there were moments -- at least to him -- where there was ample opportunity for Matthew to see a gruesome fate.

"What I liked was that he kind of went off the deep [end]. He got consumed with events, and for a guy that's very held and very in control, he loses control. That's basically what I knew and that's what I hung my hat on in a way," he said. But there reached a point where Speedman expressed a desire to channel his inner Joe Goldberg. "I was like, 'Let me kill someone, let me do something. Kill somebody. Let me get in there.' But no, not this time. We'll see. We'll see if he ever comes back, who knows?"

Speaking more specifically about Matthew's reconciliation with Theo, Speedman explained that the development was surprising simply due to "the nature of the show not having sweet, happier endings." "But when he really starts to care for his son and he wakes up to the fact that he's been a distant, not present parent and then he needs to get in there and save his son, that was interesting to me too. I was surprised though, that that happened," he acknowledged. "Doing scenes with [Dylan Arnold], he's such a sweet kid and he's such a good actor, that was really fun to do. But it was fun to beat him up a little bit too, which was great. But also, to have us come back together. He's such a likable presence that just made sense."

Speedman zeroed in on the dramatic finale showdown between Matthew and a paralyzed Joe in the kitchen as a personal highlight -- culminating in the former's memorable slap. "He deserved it," he said, referring to Joe. "He had that coming from a lot of different people. That was a great scene. It was really fun to do. It's challenging because of certain restrictions that Penn's character, Joe, had. He couldn't really speak. So it became this challenging thing for an actor, for me, to try to get information without him speaking. The visceral parts of it were the most important parts. Once you get through the revenge, the pain and the anger he has towards this man. That all boiled up and came over. It felt like a season's worth of energy pouring out into one scene. And Penn was great."

But You left things relatively open-ended in the closing moments of the season. After Joe staged a murder-suicide at the Madre Linda home he shared with Love (R.I.P.), the residents of the waspy Northern California enclave thought their nightmare to be over. Matthew is even seen reading a story about the end of Joe Goldberg on his phone months later. Of course, the truth isn't that squeaky clean as Joe was revealed to be starting anew in Paris. With Matthew and the others not knowing the full truth of what actually happened, could there be a chance he'd return in season 4?

"I don't know if I'm going to be in a beret, following him around to Paris, you know what I mean?" Speedman said with a laugh. "I don't think they're going to have me do that. But I mean, yes. It was somewhat open. I made it towards the end. I didn't close that circle with him. It's possible, but I don't know. I think they might have different storylines involved."

"If this was another type of show, you'd think [Matthew]'s still consumed with it, but they do these very specific seasons," he added. "That character, it doesn't strike me he's let go of the rope with Joe too much, you know? So it seems to me he still wants to exact some revenge at some point, but that's a different show than the one they're doing."

You is streaming now on Netflix. For more, watch below.

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