'Happy Endings' and more: Halloween on TV 2012: It�s Halloween in the office and Andy (Ed Helms) invites his college a cappella group to perform, which leads to a confrontation with his frenemy Broccoli Rob (guest star Stephen Colbert). Meanwhile, Dwight (Rainn Wilson) finds evidence that a madman is loose in the office and tries to track him down, and the first meeting of Jim�s (John Krasinski) new job causes a fight with Pam.  Airs: Thursday, Oct. 25 at 9 p.m. ET/PT on NBC.
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