The Pixar theory -COMPLETED-

Movie thirteen and fourteen: monsters university and monsters inc.

Humanity was in danger. There were not enough of us to repopulate the earth by ourselves. Because of this, we had to turn to the animals.

Some animals had learned to talk and act like humans, like the rats in ratatouille. This was caused by bnl's remaining radiation left on earth. All of these combined ( radiation, human behavior, mating with the remaining humans) made a new species: monsters.

Over time, humans were wiped out and monsters ruled the earth. However, this proved to be fatal to the monsters. With no more sources of power, the monsters would die out soon. They needed the humans for a power source.

Then they discovered the magic of wood.

Wood has had magical properties in many movies. For example, the spinning wheel in sleeping beauty. The monsters remembered this power, and made many wooden doors. These doors had the power to travel through time, therefore they could go back in time to when humans were around. They then used the human's screams to power their world and the doors.

Then came boo.

This little girl, given the name boo by sully, was not afraid of monsters. When sully opened her door, she escaped, thus leading to everything after. At the end, we see that sully has to say goodbye to boo. This was a classic heart breaker. But it doesn't stop there.

Boo now knows the power of wood. Growing up, she was never the same. She devoted her life to finding that magical place filled of wonderful creatures, to find her beloved sully. Working with top scientists, she learned how to time travel. Because she did not have the power of screams, she created a different way of making them work. She simply had to turn around, walk a few feet forwards, snap her fingers, walk back to the door, and open it. On the other side of the door would be her destination. Does that sound familiar? Yes?

That's because it is.