Though the animated series and cult hit Gravity Falls wrapped in February after just two seasons, the show's devoted following is more dedicated than ever. Thousands of people joined in creator Alex Hirsch's Cipher Hunt over the summer, completing an international scavenger hunt that culminated in the discovery of a statue of the show's supervillain. And those same fans made Journal 3, a real-life manifestation of a key book in the series, a New York Times bestseller in a matter of days.

We talked to Hirsch and Rob Renzetti, co-authors of Journal 3, about the book, the show, the scavenger hunt—and where they get all of their fabulously weird ideas.

Journal 3 is packed with hidden info and ciphers to unravel—so much, in fact, that there’s no way fans have found it all yet. Can you give a hint to something no one appears to have discovered?

Alex Hirsch: The internet never ceases to impress me. For all the talk about how the upcoming generation has a short attention span, the moment you give these kids a riddle they drop everything and suddenly work together in perfect harmony like a military-level SWAT team to crack the code. It’s incredible. That being said, sometimes fans are often so focused on code-cracking they miss what’s in plain sight—the actual text of the journal! There are connections in there that even the savviest fans still have yet to notice.

Journal 3 reveals new details about most of the major characters, like Ford's Smash Mouth tattoo and the fact that Soos glues on his chin hair. How much of that existed as character development during the series, and how much backstory did you create just for the Journal?

Rob Renzetti: Alex could probably give you a more encyclopedic answer to this question. I think a lot of Stan’s backstory was something that he had in his back pocket during the whole run of the series. Other smaller things were definitely invented for the book. The chin hair bit was something I came up with as a throwaway joke that I thought said a lot about Soos. 

AH: I've had the backstories for many of these characters in my head for a long time. Especially Ford and Bill, and how Bill played to Ford's ego and almost destroyed the world in the process. Of course we still improvise and invent new things along the way. That’s the fun of writing—finding chances to surprise yourself. Ford's tattoo was a surprise to me, too—courtesy of our awesome illustrator Andy Gonsalves.

Courtesy Disney Publishing

One of the fun things about the Journal is that we get to dive deeper into some of the episodes. For example, Ford chronicles a few of the other dimensions he experienced while he was in the portal. What inspired those? In particular, the "M" dimension stood out to me as something that must have a story behind it.

AH: While writing season two, we wanted to send our characters through the portal into the multiverse but never found a way to quite make it work with our storyline. There were tons of drawings and jokes we came up with during our brainstorms—including the annoyingly pointless M dimension. We loved the idea of someone as scientific and rational as Ford having to fight his way out of what was essentially a Sesame Street segment teaching you about the letter M. It would drive him insane.

RR: The M Dimension came out of an unused story where Mabel went through the Portal and the Pines needed to go search for her. We were brainstorming ideas for alternate dimensions and the M Dimension was the most delightfully silly thing we could imagine.

Much has been made over how much creative control you were able to retain even though Disney’s Standards and Practices is presumably pickier than most. Was there anything you really had to fight for? Did you lose any of those battles?

AH: One day I'd love to release a coffee table book of all the crazy notes I got from Disney Channel's S&P and legal department. To give you a sense of what I was up against, one time I was told, "Make sure the target that Wendy throws a dart at doesn't resemble the target from the store Target." To which I had to reply: "The target isn't the target from Target. The target is a target."

Welcome to my hell.

Was anything vetoed from the Journal?

RR: I don’t remember any idea that we came up with being vetoed or changed. Disney Publishing is particularly awesome that way.

AH: Disney Publishing has been incredible. They didn't give me a single note on this journal. They understood the tone of the show, believed in my vision, and more importantly, trusted the intelligence of our audience. Working with them has been a dream come true. I wish the gatekeepers in kids TV were as savvy and in tune with the audience as those in Publishing.

Courtesy Disney Publishing

The Cipher Hunt was such a fun, interactive way to keep fans involved. Where did you get the idea?

AH: I spent 90 percent of my childhood playing SNES and N64, and my favorite games were the ones packed with secrets. I remember spending one summer being utterly obsessed with trying to get the legendary unreachable "Ice Key" from Banjo-Kazooie. What was so brilliant about that item was that it was literally impossible to get and just was there to torture players. Or so people thought. Until years later, someone discovered a code that let you find it. I remember thinking that if I ever had a chance, I wanted to create something that gave fans the same feeling. A last mystery after the game is over. Something so hard to find it reaches legendary status. Launching the hunt and watching the fans team up all over the world to find the clues was one of the most fun things I've ever done.

Do Mabel and Dipper's names have any special significance?

AH: I imagine that [their] parents see themselves as slightly counter-culture and chose purposefully archaic names just so their kids would stand out among the 12 Chrises and 14 Jessicas in Dipper and Mabel's preschool.

You’ve talked a lot about the real-life inspirations for many of the main characters, but I haven’t seen much about where McGucket came from. I thought it was interesting that Journal 3 showed that not only was he once a genius, he was actually the voice of reason before he got fed up with Ford.

RR: McGucket started as a throwaway joke character in "Gobblewonker" and just grew and grew in importance as the series went on. It just made sense to us that a character with such scientific and technological skill would be tied to the creation and the creator of the Portal.

AH: McGucket originally started out as just a wacky stereotypical hillbilly and a chance for me to scream into the microphone. (He was originally called Old Man McGuffin, which is a literary trope meaning something unimportant that sets a plot in motion.) But when our writers got deeper into the story we discovered that there was an exciting opportunity to connect him to our characters’ pasts and destinies. I'm very glad we did—giving Ford a friend humanizes him, as well as deepening the tragedy when they part ways.

Courtesy Disney Publishing

What's next for you both?

AH: Right now I'm developing a few different projects for a few different places, but it’s too early to comment on any of them. Like Grunkle Stan, I like to stay a man of mystery until the right moment to fleece rubes emerges once more.

RR: I’m serving as executive producer on a new show for Disney TV called Country Club created by the very talented Houghton brothers. It’s about a country family’s oversized adventures in the Big City.

Finally, a question from Lydia, my superfan 6-year-old: "Where do you come up with all of the weirdness?"

AH: I didn't come up with the weirdness. I was born in it. Molded by it.

RR: There is an unlimited supply of weirdness in the weird world around you and inside your weird self. Lots of people try to ignore it and lots of people try to stamp it out. But the best people allow themselves the freedom to be weird. Be the best, weird person you can be.