Professor Z, Marshall and others in “Unfinished Business”

Let's recap what I know.

Well, I became invisible, Lucas aged sixty five years, Corrine lived the same day over and over, Josie and Vaughn went back in time.

What we know is that the school has issues.

I'm telling you it's all connected.

Okay. But how?

I don't know. But if we're listing the strange things at this school, don't forget about the black hole.