A dream demon called Jeremy was forced to flee the dimension due to an unexpected rein of Bill Cipher's descendant Walter, in a parallel universe where bill was defeated 30 year's earlier before the twin's Mabel and Dipper's appearance. Jeremy seeks the missing race of cipher's (who had escaped to Gravity falls, in human form. The twins encounter the demon, but little did they know that their new found friend is one of their greatest challenges yet...