When they get back to the car, they find that they've locked the door, which means they're going to have to run around like crazy to find their way back to where they left off. When they finally get to the spot where they parked, they realize that they can't just leave the door locked. They've got to get back into the car before the police find them. They lock the door so they can get into the trunk, but they don't have enough room in the car for the two of them to fit in. They decide to go inside the trunk to hide from the police, since it'll be easier for them to catch up with them later on.