The series follows the adventures of Dipper Pines (Jason Ritter) and his twin sister Mabel (Kristen Schaal), who are sent to spend the summer with their great-uncle (or "Grunkle") Stan (Hirsch) in Gravity Falls, Oregon, a mysterious town full of paranormal incidents and supernatural creatures.

On November 20, 2015, Hirsch announced that the series would conclude with its second season, stating that this was "100% [his] choice" and that "the show isn't being cancelled – it's being finished" and was reaching its intended conclusion.

The series attracts a broad and passionate fandom, is considered to be an influence for many animated shows that followed it, and spawns a variety of official merchandise.

For their summer vacation, 12-year-old twins Dipper and Mabel Pines are dropped off from their home in Piedmont, California, to the fictitious town of Gravity Falls, Roadkill County, Oregon, to spend the summer with their great uncle Stan Pines (often shortened to Grunkle Stan), who runs a tourist trap called the "Mystery Shack".

[12] Hirsch graduated from the California Institute of the Arts, and was hired to work as writer and storyboard artist for the Cartoon Network series The Marvelous Misadventures of Flapjack, where he was paired up with Pendleton Ward, the creator of Adventure Time.

[12] Afterwards, he moved on to co-develop the Disney Channel animated series Fish Hooks; shortly before he pitched Gravity Falls, which was subsequently green-lit.

"[17] In an interview with Oh My Disney, Hirsch claimed he already had the beginning, middle, and end of the story for Gravity Falls planned out when he first pitched the series.

Club that during the production of season one, a typical episode was conceived in a room reserved for writers, where a simple synopsis was presented, and from then on dramatic structure was defined, and the plot was modified to include a character-driven subplot, which Hirsch expressed as "the hardest thing ... to find a character story that actually uncovers, explores, or pushes tension—on something our characters care about—that is properly explored via the magic or monster or impossibility of the week.

[25] On November 20, 2015, Hirsch announced that the series would conclude with its second season, stating that this was "100% [his] choice" and that "the show isn't being cancelled – it's being finished" and was reaching its intended conclusion.

[104][105] Gravity Falls received critical acclaim with praise directed at its writing, characters, voice acting, animation, humor, and multi-generational appeal.

[109] The website's critical consensus for season one reads: "Gravity Falls' warm humor and bright performances elevate this children's cartoon to a show for all ages",[108] while the website's critical consensus for season two reads: "Gravity Falls continues to blend old fashioned storytelling with a modern sense of humor to create a uniquely enjoyable viewing experience.

[110] In his review, David Hinckley of New York Daily News called Gravity Falls "quirky and endearing", and offered praise for the character of Mabel Pines.

"[115] Michelle Jaworski writing for The Daily Dot described Gravity Falls as "[A] classic summer story woven into a smart and addictive show tackling the paranormal, the supernatural, and the pains of growing up.

"[116] IndieWire's Michael Schneider said "Gravity Falls is a kids' show so dense with mythology, pop culture jokes, Easter eggs, and mystery that grown-ups were often more invested.

"[118] Donna Dickens from Uproxx said "Not only does Gravity Falls deal with the inexplicable supernatural occurrences in the town, the whole thing is just one big puzzle of secrets waiting for fans to uncover and solve.

Club said "With a complex mythology and a deep lexicon of cultural references, there's sophistication to the show's epic storytelling that immediately drew the attention of a wider audience.

"[120] Liz Baessler writing for Film School Rejects said "Gravity Falls is an exceptional kids' show — brilliant, hilarious, and carefully crafted.

[122] Brian Tallerico from RogerEbert.com said "Gravity Falls deserves to be in the conversation with Bob's Burgers, Rick and Morty, and BoJack Horseman when people discuss the best animated programming of the '10s.

"[123] Collider's Joel Pesantez said "Gravity Falls exemplifies Disney's ability to appeal to all ages with captivating mysteries and a diverse, relatable cast.

"[124] Abigail Stevens of Screen Rant said "There is so much to learn about from Gravity Falls' two seasons, which pack in plenty of laugh-out-loud and tear-jerking moments."

Stevens further added, "Gravity Falls also created something of a cult of mystery, encouraging viewers to find hidden codes in each episode and giving rise to a fandom that was able to predict the show's biggest twist.

"[125] Lilian McDonough from CBR called Gravity Falls "the undeniable peak of Disney Channel cartoon history" and said "by utilizing an overarching narrative to an extent that no prior Disney cartoon had and funneling that into an intricately crafted and endlessly interesting location overflowing with lovable and hilarious characters, Gravity Falls broke every barrier imaginable and made what, for good reason, became one of the most beloved shows of the era.

[131] In 2015, Gravity Falls accounted for Disney XD's top seven regular animated series telecasts of all time among kids ages 6–11.

[131][132] Gravity Falls ranked as Disney XD's number 1 series of 2015 across all target demographics[133] with an average of 1.8 million viewers per episode.

[134] The series finale "Weirdmageddon 3: Take Back The Falls" beat the ratings record previously held by "A Tale of Two Stans" becoming Disney XD's most-watched telecast ever, with 2.47 million viewers in the United States.

[134] Marketing for The Book of Bill in January 2024 revealed that Gravity Falls was one of the top 50 shows with the most hours watched on Disney+ of all time and that more than half of the viewers were families with kids over the age of thirteen.

[135] Gravity Falls has been considered to be an influence for many animated shows that followed it, including Steven Universe, Star vs. the Forces of Evil, The Owl House, Amphibia, and Rick and Morty,[136] the latter three of which with it features numerous Easter egg crossovers.

[153][161] On August 3, the statue was removed by authorities due to a property dispute[154][162] and was temporarily held at the Reedsport police department while Hirsch arranged for it to be moved somewhere else.

[162] By August 5, the statue temporarily ended up in Bicentennial Park in Reedsport,[163] before being permanently relocated to Confusion Hill in Piercy, California a few weeks later.

Disney ultimately passed on the project, as the studio felt the show "wasn't big enough to warrant [a film]"; Hirsch stated that he was still interested in the idea.