13 Reasons Why is one of the most popular shows of 2017. And when shows are this popular, fan theories come in large supply.

*SPOILER ALERT* If you haven't watched the series, turn back now.

There are so many fan theories about 13 Reasons Why, it's honestly hard to keep track.

There's the theory that Hannah's story is over and we won't be seeing her in season two. There's also the theory that Tony doesn't actually exist and is just an angel that stops in to help Clay listen to the tapes. Sounds crazy, but also sounds kind of legit.

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With so many fan theories, it seems like the viewers left no stone unturned when it comes to hints in the plot.

I had the opportunity to speak with the show's production designer, Diane Lederman, and she says there are lots of tiny details fans missed.

A production designer's main responsibility is to create the entire world of the show and make you believe it's real, according to Lederman.

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She said, "When you get it right, people don't notice. When you get it wrong, they absolutely do," meaning "the devil is in the details," and every single thing you saw on the show — whether it be the rocks in Jess's rock collection or the designs on the walls at Monet's — was carefully curated by Lederman and her team.

She said,

Production designers are responsible for the entire look of a show, whether it's a film or it's a TV series, or even something that's commercial, the production designer is responsible for what the tone of the show is going to look like in the broader sense. In the more detailed sense, is finding, choosing locations, designing the layout of sets, working with the set designers, scenic artists, carpenters, the set decorator, giving everybody the direction of what their jobs are supposed to be. My job is the big vision that I download to them, so that they can in turn do their job.

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She continued,

Selling reality is pretty much the most important part of my job. If people don't believe the environment, if people don't believe what you're telling them, they're not going to be able to immerse themselves in the story. If sets don't look real, it's going to be very, very hard for people to let go and just get into the reality of the story.

So yeah, if it weren't for Lederman and her team, you wouldn't have been able to come up with all of your theories about the plot because you would've been too distracted by the physical look of the show.

Color plays a big role in this. It sets the tone of any show or movie, and it has the power to completely draw the viewer away from the plot if it's not the right choice for the given circumstances.

And that's why, according to Lederman, everything at Liberty High was blue.

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The lockers, the letterman jackets, the walls in the gym, the cheerleading uniforms, the locker room, Clay's bedroom -- they're all a shade of blue. And that color had a big meaning throughout the entire show, as it was meant to reflect the tone of everything that was going on.

That color is intended to reflect the melancholy, the sadness, the depression, the dark undercurrent of what's going on inside the school, Lederman explains.

It was a very cool palette, as a general sense. Blue is not a color I often use. Certain shades of blue photograph terribly, certain shades of blue are beautiful when they get more into the blue/greys. But I thought blue was a very, just because of the emotional intention of the color, was a good choice for this show. And everything having to do with Liberty High was shades of blue, and everything having to do with Clay was shades of blue.

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Hannah and Jess were different, however. And that was intentional, given that their stories and what happens to them are the darkest out of any other character. Lederman said,

Hannah's palette was like lavenders and purples. That's a color that evokes mystery, and it's a very feminine color, and it was just the perfect color for her skin tone as well, so Hannah's world was all purple. Very soft pinks were for Jessica, because she was, I don't want to say the princess, but she started out as the prissy character before she went dark. And I thought it would be very interesting to contrast her behavior and what happened to her as an adult with this very childlike bedroom and princess sort of bedroom that she had. So her colors were predominantly pink for her room. But as a general rule, we used a very cool palette.

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Colors are also used to reflect character development, Lederman explains. So the worse Hannah's mental health becomes, the darker her clothing. The same goes for Jess and Clay. Their clothes get darker in each episode. Lederman said,

Making it real is what's important. A lot of [tiny details meant to reflect character development] goes unnoticed. Jessica's rock collection that was discussed that was in her room, the stuffed animals were chosen in a very specific way. In Hannah's room, all the drawings on the wall were thought about, sort of to reflect her emotional journey. In Clay's room, all the robots, all the science paraphernalia and astronomy posters were to sort of emphasize his somewhat geekiness at one point. All these things are chosen very carefully. And without those details and without trying to show the backstory of all these different characters, sets don't feel real.

Although Hannah and Jess's clothes changed as time went on, their rooms didn't. And that was intentional, as well, according to Lederman.

She wanted the rooms to remain unchanged to show that you would never expect such awful things to happen in such innocent-looking bedrooms. And that's exactly the point: you never expect such horrible things to happen in such safe-looking places.

The town looks safe, the school looks safe, the homes look safe, the bedrooms look safe, but just because something (or someone) seems fine doesn't mean they are.

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And that's the whole point of 13 Reasons Why: Someone might not look like they're in pain, but that doesn't mean they aren't. You have to look under the surface and not assume that everything is fine based on its appearance. Lederman said,

For that matter, most people wouldn't imagine this would happen to the average high school girl. And apparently this happens often enough. And the whole point of this show, the point of this story, the point of Jay Asher's point, is to bring these stories into the public, or make people aware that these things happen. And if it enlightens people and maybe stops that from happening to one more person, then we were successful in what we did.

There's a lot of controversy surrounding the show because of its unapologetic portrayal of the reality of rape and suicide. The main critique is that Hannah's tapes are basically the ultimate revenge suicide fantasy, making the show dangerous for potentially suicidal viewers to watch, especially those in high school.

Lederman addressed this controversy by saying,

I know there's a lot of controversy about it, but I applaud it because it means people are talking about it and they're talking about the subject matter. And that's really what's important. Nobody wants to talk about it. Nobody wants to deal with it, of course not. Very close by to where we shot, there was a town where, in the last three of four years, there were about six suicides, high school students. So it is important that people are talking about this.

13 Reasons Why has its own crisis site called 13reasonswhy.info, where you can find help if you or someone you know is struggling with thoughts of suicide.