Andy Bernard (Ed Helms)
First seen- Season three, episode 1 Andy is introduced as Jim’s obnoxious new coworker at Dunder Mifflin – Stamford.
Last seen- Season nine, episode 24/25 After becoming the new Michael Scott and then inevitably getting fired, Andy comes back to say he’s doing well and has a fiancée.
Nope, that theory is debunked :)