The Office: Duel (1/15/09)
Thanks to Michael’s running mouth, Andy finally learns that his beloved Angela had an affair with Dwight, a discovery that incites the two romantic rivals to square off. Elsewhere, Michael is on edge about a corporate appointment with bigwig Wallace.
I really think this is what leads the spin-off and Andy leaves to go to the other show. Does anyone even know when the spin-off is coming?
Update: You can now stream this whole episode after the jump.