(Gravity Falls starts now)
What first struck Twyla about Gravity Falls when she thrust the TARDIS door open was how utterly normal it seemed at first glance.
A small town was all she really saw when she opened the door to see the town square. A slight chill passed through the air as a result of it being in the northern United States, but it was easily ignored, especially for a girl who was used to it.
There was nothing interesting about it at first glance, but really, Twyla had no idea what she was expecting. Something a little bit more interesting, maybe. Is this seriously Gravity Falls, Oregon? After the thought was completed she repeated the question to the Doctor.
"Of course it is, Twyla!" the Doctor replied, pulling on his tweed jacket. "The TARDIS doesn't lie, you know. There is rarely anything interesting going on on the surface."
That makes sense, I guess. "Can I walk around?" she was holding back the fangirly squeal bubbling and threatening to spill over - after all, this could always just be a small town that Gravity Falls was named after.
"Sure, but don't wander far." the Doctor finally replied after deciding that nothing dangerous was going on right at that moment. "I'd like to be able to find you if something happens."
Twyla nodded and ran off. "I already know what I'm looking for!" she called over her shoulder.
Sure enough, after running for a while, she found the run-down building that could only be one place. And the broken sign depicting MYSTERY HACK guaranteed it.
Finally, after she noticed that nobody was watching, Twyla let herself have a fangirl moment.