From Dorothy's ruby red slippers in The ??? ???? ????? ?????Wizard of Ozto McLovin's fake ID in Superbad, the prop hall of fame is abundant with knick knacks that culturally define the movies and shows that made them. Amidst them all is a newitem of interest. One that's occupying its own special corner, ominous fog clouding its periphery, icon status arguably unmatched: Joe's box in You. 

The doomed keepsake's flown across the world from New York to California, and all the way to London, accompanying Joe (Penn Badgley) like a friendly sidekick. It's perhaps the only reliable constant in his life. And while Youoffers gut-wrenching thrills on a silver platter, nothing comes close to creating that dreadful sinking feeling than seeing the return of Joe's cage. It prepares us for what's to come, even though we all know how that usually ends. 

Considering the cage's relevancy in the You-niverse, it's only fair to ask what it's actually like being in it. Is it actually real? Does it get kind of comfortable at some point? And more importantly, how is Joe packing it with him across the world? In an exclusive interview with Mashable, Season 4's surprising cage tenant Tati Gabrielle answered all of our questions about Joe's box, including how being in it brought her in touch with Marienne in ways she couldn't have imagined. 

Being in Joe's box is a lot like having Stockholm Syndrome. 

"I spent a lot of time shooting in the box," Gabrielle shared. "I didn't really come out of it unless I had to pee, basically. So I was spending anywhere from six to 10 to 12-hour days just in the box." Her long hours on set brought her closer to Marienne's reality by virtue of simply having to be in the box all the time. 

"Yes, at first it's a cage, and it's you being held captive. But at some point, it's a human tendency to make yourself comfortable," she explained, on adapting to the box. "It turns into some sense of home, sort of like [having] Stockholm Syndrome, so I wanted to get as comfortable as possible."

"We shot all of my cage stuff over the course of about two and a half weeks," she recalled. "And even after the first week, I could start to marry Marienne in her feelings. Even as things got drearier and darker for her, and as the demons started to come up, I could match her environmentally."

The box also had its own transformation this season. 

In a fun behind-the-scenes tidbit, Gabrielle shared that this season's box was actually a new one.

"Penn [Badgley] kept complaining about it. He was like, 'This is a different material than last year's box,' because the glass walls were too thick to be heard inside and out." (Of course You's actors have become so acquainted with the box that they can tell when it's received a glow-up.)

In addition to Marienne's scenes being emotionally harrowing, filming proved to be surprisingly difficult because of the new box. "The scenes where Nadia's [Amy-Leigh Hickman] right up the glass, I could hear her. But otherwise, if we were six feet apart and speaking at normal levels, it's harder to be heard. My voice was raspy through that time, so both her and Penn were like, 'HUH?! You gotta speak up, Tati!'"

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But the question that's on everyone's minds remains: How is Joe's box moving with him across the world?

"We actually talked about that on set. We all guess he just ordered a new one. Joe's got his plug now, you know; he just calls him up," Gabrielle mused.

So, there you have it. Ordering your very own box of doom is as easy as buying a vacuum off Amazon, so if you're keen to experience your own time in a glass cage, you know what to do. 

YouSeason 4 is now streaming on Netflix.