Return to Gravity Falls

Return to Gravity Falls is the first episode of the series Gravity Falls: Secrets Unleashed.

Main Synthosis
It's been a full year since the events of the original Gravity Falls series, and now Mr. & Mrs. Pines have decided to send their twin children, Dipper and Mabel, back to the mysterious town of Gravity Falls to spend another summer with their great uncle Stan at the Mystery Shack, and it seems like Gravity Falls's secrets have been unraveled. But then a mysterious final note on Dipper's book, 3, suddenly appears, warning of a big threat to not only Gravity Falls, but to the world, that can only be stopped with the secrets contained in all six books. And to uncover their first clue of the whereabouts of the first book, Dipper, Mabel, and Soos must track down and defeat the deadly Manticore of Gravity Falls. ..

End Credits Cryptogram
YBTXOB QEB QOLABD, which when put through the Caesar Cipher, becomes BEWARE THE TRODEG.