1. Stanley died and the office is his hell.
2. Jim cheated on Pam with Cathy in Philadelphia.
3. Everyone was suffering from radon poisoning.
4. Kevin Malone embezzled money from Dunder Mifflin.
5. Jim is a sociopath.
6. Dwight has delusional disorder.
7. And finally, the Scranton Strangler might be Creed...
