Penn Badgley reveals he had lead in his pants during You underwater scene

Warning: This post contains spoilers from You season 4, part 2.

Just when you thought Joe Goldberg (Penn Badgley) wasn't the murderer this season...

With the release of You season 4, part 2 we now know that the true killer this season was none other than Joe Goldberg himself. Part 1 did its best to trick fans into thinking Joe had changed his ways and that the real killer was Rhys Montrose (Ed Speleers). However, the truth was revealed at the end of season 4 episode 7. In a plot twist fans might not have seen coming, Nadia Farran (Amy-Leigh Hickman) finds Marienne Bellamy (Tati Gabrielle) trapped in Joe's infamous box. Soon after, it comes to light that Rhys isn't the murderer at all, but a figment of Joe's imagination that he created during a psychotic break.

"There's this thing where you get to see Joe from another person's eyes which we've never really seen before," Penn Badgley tells EW. "And you realize this whole thing is almost this romanticized version of him. Maybe. And then you also have Rhys, which is a fun way to make literal the metaphor of the inner child or the ego. To me, by the close of the season, I think you've really gotten what you came for."

Courtesy of Netflix Ed Speleers as Rhys, Penn Badgley as Joe Goldberg

Turns out the idea of a "romanticized version" of Joe Goldberg came almost a whole season prior, at least that's what Badgley believes. Badgley continues, "The truth is in episode 3 of season 3, there's that Joe-on-Joe thing where I play two people. That was really fun and I think that planted the seed. I have no idea how much I did or didn't influence this, but I thought that's the direction it could go. I knew that it was going to be some kind of Fight Club twist, which I loved purely on the surface, but also at the ground floor."

Bringing to life Joe's "inner demons" in the form of a fictional person was the most logical way to go when it came to the season's direction. Having this side of Joe take form allowed him to fully see the truth about who he is at his core. "The show is called You right? I watch YOU walk into the bookstore, and I'm obsessed with YOU, and I'm going to put YOU in a box. But it's all because he can't look at himself, so finally he realizes it's not you. It's me," Badgley says. "That age old line. It's really what this show has been on an arc toward so it's so perfect. It didn't hit me as a shock, I was like, 'Oh that is going to be really good.'"

In addition to the Rhys-is-actually-Joe surprise, we also got a surprise visit from Joe's former love interests Guinevere Beck (Elizabeth Lail) and Love Quinn (Victoria Pedretti) in a dream sequence. Badgley had the pleasure of not only acting alongside his former costars, but also directing them for the pivotal episode.

"It was very intuitive. It was very natural," he says of directing. "The only challenge was not being able to be in two places at once, trying to prep an episode while shooting an episode. Trying to edit an episode while shooting another episode. It was pretty bananas. Being able to direct our old friends Elizabeth [Lail] and Victoria [Pedretti] was nice as well. I especially enjoyed being able to direct the other actors. The irony in television is that you don't have that much time where you get to work directly with the actors. It was very special."

courtesy netflix Victoria Pedretti in 'You'

In addition to giving us the return of some of our series' favorites, You season 4 also brought in a well-known face with the introduction of Tom Lockwood (Greg Kinnear). At first it seems like Joe might have met his match in Lockwood, Kate's (Charlotte Ritchie) father, since he seems to know all of Joe's secrets. However, that doesn't turn out to be the case.

Kinnear's character ultimately reaches a gruesome end at the hands of Badgley, but that doesn't mean the actors themselves didn't have a fun time on set. "I remember the first rehearsal we had and I thought 'This is great!' I don't get to act with men a lot and I don't get to act with older men hardly ever. Like a mentor. It was just nice. For him to be such a talented actor and so experienced was great," says Badgley.

After killing Lockwood, Joe quickly realizes that he'll never be able to outrun the truth that he's a murderer. No matter how he might try to spin it, whether that be blaming it on Rhys (the fictional embodiment of his dark side) or telling himself that it's all for "good" and he's doing it to "protect the ones he loves." That discovery then leads Joe to the top of a bridge ready to jump to his death. And then he does.

Badgley explains that shooting that sequence was unlike anything he has ever done. "I'l tell you what. I was having weird flashbacks to [being in the water] the other day. I got panicky," he says. "That was very intense! I had lead in my pockets, lead in my boots, fully clothed at the bottom of a 20-foot tank, so it's not easy to swim to the top. You're not a trained diver. Then they say, "action" and you know all the protocols so you know what to do, but then they swim far away so that you can't see their bubbles. Then you're underwater [by yourself essentially] where the stakes are so high. It's really crazy actually. I found it really hard to act because you lose your air so quickly. I think some people would have a full-on panic attack. It was just so claustrophobic and you're completely at the mercy of people you don't know and physics. I was good with it while we were doing it, only later was I like 'Holy s---. That was crazy!'

"There was even one part where I started choking," Badgley continues. "I was forcing myself to not choke cause if I choke, I might drown. It's a scene! I'm not saving anyone. Just acting!"

In the end, the underwater acting paid off. The scene ultimately leads Joe to believe that he was "born to give Kate the love that she deserves." Of course, Kate, who doesn't know anything from Joe's past, takes him back so the duo can begin their "loving" relationship.

So where does this leave Joe now? "I guess it does put Joe kind of back where he started, but now he has unlimited resources," Badgley says. "He use to hate people for the money they had and the power they had and the families they had and the hypocrisy they embodied and now he is all of those things."

When asked what this new status means for Joe's future, Badgley replied, "I sort of hope he's unhinged now. It would be fun."

You season 4 is streaming now on Netflix.

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