The Office (Season 7, Episodes 5 and 6)
Ace salesman and consummate cool guy Danny Cordray causes a slight disturbance at Dunder Mifflin, first by beating the combined efforts of Jim, Dwight, and Michael during a sales call, then by joining the company. See, four years ago, Danny went on a couple dates with Pam but then never called her back, and so Jim and Pam get super passive-aggressive with him about the whole thing. Hostile work environment!