It had been many years since the end of the most amazing summer. Dipper remembered that time fondly, and he would often talk to his sister about the once in a lifetime events that they had lived through. Now they were heading back one last time before they had to head off to college and become adults.
Mable drove most of the way, hoping to surprise their uncle and grandfather with their presence. Whilst Dipper sat in the passenger seat, reading over one of his uncle's journals to get in the mood for the trip. A few hours passed with only Mable's incessant pop music blaring on the radio to fill the silence. It began to rain about the time they had gotten into town. Which made Dipper feel nostalgic. He looked out the window, a large grin filling his features as he saw the familiar sign, "Gravity Falls." He read out loud.
Mable giggled in her girlish way, "Man, you really missed this place, huh?"
Dipper turned to her, excited, "Of course I did! It's amazing here! I can't wait to see Soos and grandpa, and grunkle! It'll be just like it was when we were kids! Magic, and mysterious!" His excitement succeeded in making his twin smile.
She glaced over at him, then back to the road, giddy herself, "I wonder if they'll be happy to see us."
Dipper sat back, "Of course that will. They love us, and they can't have very much fun without you."
"True, true." Mable laughed, "Without you they have no one to make fun of."
Dipper took the challenge, "Very funny Mable, and without you they wouldn't have someone to bedazzle everything."
She turned to retort, but just as she did, Dipper tensed, and yelled, "Mable look o-"
When she snapped back she saw a shadow in the middle of the road, causing her to swerve, and before Dipper finished they hit something so hard that both hit their heads on the dash, and steering wheel. This caused them to lose conciousness, and the worst part was, that nobody knew that they were supposed to be there.