Question: what are all the halloween episodes of the office?
Answer: Season 2, Episode 5 - "Halloween" ... , Season 5, Episode 6 - "Employee Transfer" ... , Season 6, Episode 8 - "Koi Pond" ... , Season 7, Episode 6 - "Costume Contest" ... , Season 8, Episode 5 - "Spooked" ... , Season 9, Episode 5 - "Here Comes Treble"