Twins Dipper and Mabel Pines visit their eccentric great-uncle for a summer in Gravity Falls, Oregon, where he operates the world's most bizarre museum. As soon as the twins arrive in Gravity Falls, they discover something amiss in the remote town.

When Dipper and Mabel hear rumors of a sea monster that lives at the bottom of the local lake, they enlist Soos to take them on a boating expedition to prove it really does exist.

When someone tampers with Mabel's life-size wax statue of Grunkle Stan, she and Dipper set out to find the culprit. Meanwhile, Grunkle Stan mourns over the loss of his wax doppelganger.

Dipper and Mabel discover that their seemingly cherubic new neighbor, Lil' Gideon, happens to be the town's adored psychic. But when Lil' Gideon guilts her into dating him, she and Dipper soon learn that his cuteness can fade all too quickly.

Dipper is invited by Wendy and her teen friends on a trek that leads to an abandoned convenience store that may be haunted.

In a quest to attain manliness, Dipper ventures into the forest to battle the notorious Multi-Bear. Meanwhile, Mabel tries to teach Grunkle Stan how to be attractive to women, particularly the waitress in the local diner, Lazy Susan.

Stan throws a big weekend party to promote the Mystery Shack. Dipper makes clones of himself to impress Wendy. Mabel fights for the Party Queen title in honor of her two friends.

When Dipper and Mabel discover evidence that the reported town founder is a hoax, they set out to expose the historical cover-up and prove that Mabel's silliness is not a bad thing.

Dipper wants to correct a mistake he made in the past with assistance from a time machine. Mabel is overjoyed when she wins a pet pig at a fair.

After being challenged to a video game battle by Robbie, Dipper is shocked when his favorite playable fighter, Rumble McSkirmish, comes to life to defend him. But Dipper soon loses control over Rumble McSkirmish and has to find a way to stop him.

Dipper is self-conscious that Mabel is taller than him and seeks a magic solution. Meanwhile Lil' Gideon takes advantage of Dipper's and Mabel's height discrepancy.

Dipper and Mabel go trick-or-treating in the summer and encounter a candy-loving monster who threatens to devour them if they don't bring him sweet things to eat.

Stan leaves Mabel in charge of the Mystery Shack while he is gone and the power goes to her head.

While Stan, Dipper, Mabel and Soos are falling in a bottomless pit, they tell stories to pass the time.

When Mabel befriends a cute merman trapped in the public pool, she's determined to help him out. Meanwhile, Dipper decides to volunteer as a lifeguard to see Wendy.

The twins discover a hidden room inside the Mystery Shack and compete over who should have it.

When Mabel discovers that her favorite boy band is actually a bunch of imprisoned clones, she sets them free, only to decide on keeping them for herself. Meanwhile, Dipper is convinced that Robbie plans to brainwash Wendy with a secret message hidden inside one of his songs.

When Waddles is snatched by a prehistoric beast, Dipper, Mabel, Stan, Soos, and Old Man McGucket must journey to a mysterious land trapped in time to rescue him.

Dipper, Mabel, and Soos must travel through Grunkle Stan's mind to defeat a tricky dream demon summoned by Lil Gideon.

Li'l Gideon swindles the Mystery Shack away, forcing Grunkle Stan and the kids to move in with Soos. While Stan weighs how he can still care for his grandniece and nephew, they decide to take on Gideon.

The Pines family is starting to get everything back to normal after the Lil' Gideon incident. They throw a “Mystery Shack Is Back” party, but some unwelcome guests intend to crash it.

Dipper’s secret journal pages lead him and the gang to the author’s hidden bunker where they find themselves face-to-face with a mysterious figure from Gravity Falls’ lore.

After being belittled by Pacifica one too many times, Mabel challenges her to a miniature golf-off which gets a tad out of control when some local residents offer their help.

Mabel decides to put on a sock puppet rock opera to impress a local puppeteer, but her show goes awry when Dipper's drive to uncover more of the journal's secrets leads to a supernatural disaster.

Soos needs a date for his cousin Reggie's engagement party and looks to a dating simulator game to help him talk to girls.

In three separate mysterious tales, Stan is cursed by a Witch, Waddles accidentally eats a bowl of brain-enhancing jelly and builds a machine that allows him to speak, and Mabel faces her fear of claymation.

The kids, along with Old Man McGucket's help, discover there is a secret society in Gravity Falls.

Blendin returns to face off with Dipper and Mabel in a futuristic battle that could trap them forever in time jail.

Mabel takes matchmaking too far when she steals a love potion from a real Love God.

Pacifica enlists Dipper’s help to rid the Northwest Mansion of a ghost before he wreaks havoc on her fancy party.

After agents Powers and Trigger take Stan into custody, Dipper and Mabel begin to wonder how much they actually know about their Grunkle Stan.

Cornered underneath the Mystery Shack, Stan must finally reveal the secrets of his past and his mysterious portal to Dipper and Mabel.

Dipper finds an unlikely friend to join him with his newest obsession, a board game called “Dungeons, Dungeons & More Dungeons.”

When Grunkle Stan decides to run for mayor, Dipper and Mabel have their work cut out for them trying to turn their gaffe-prone uncle into the perfect candidate.

A new threat leads Mabel to venture into the enchanted realm of the unicorns. Meanwhile, Dipper learns an unexpected twist about the enigmatic Bill Cipher.

Grunkle Stan takes the kids with him on a road-trip to sabotage all the other tourist traps in Oregon.

Mabel makes plans for her and Dipper's 13th birthday party; Dipper ventures below the town and discovers its most shocking secret.

Bill has returned to take down the Pines family. But this time he has brought some of his friends with him.

Dipper, Soos and Wendy must save Mabel from a strange new world, while Bill's forces plan their next move.

Ford discovers Bill’s true motives and a final confrontation with Bill leads to the Pines family’s ultimate fate and greatest sacrifice.