Mickey Madhouse

You realize that you can take a break from your torture and go on one of your favorite rides, space mountain. You walk through the dark paths that are usually filled with people and are suddenly shocked when something interrupts your path. Your face soon meets the ground. Good thing nobody was there to see you embarrass yourself. You stumble again as you try to get up. Since the room is pitch black, it is incredibly hard to see your surroundings. As you start to walk again, you feel lighter, as if something you were carrying was no longer with you. You realise that you had dropped your wallet and you reach into your pocket to find your “flashlight”. Right after you find your wallet, you look around on the floor to see what you had tripped on. You notice a small box in the corner. You realize that this is the reason you tripped. You are all of a sudden curious about what is the significance of the obstacle that made you fall. You open the box and there lies a small piece of paper. Again, same texture, color, and handwriting as the other three. Right under this note, there is a tarnished silver key. You read the letter and it says:

You are smart enough to make it this far,
Take the key and find the car