 The title is a reference to Andy 's college a cappella group , which had previously been alluded to in the series , but never actually shown . The episode also marked the final Halloween installment for the series . " Here Comes Treble " received mixed reviews from television critics , with many mainly criticizing Andy 's characterization . Others were more complimentary of the episode 's subplots . " Here Comes Treble " was viewed by 4 million viewers and received a 1 @.@ 9 / 5 percent rating among adults between the ages of 18 and 49 , ranking third in its timeslot . The episode , however , ranked as the highest @-@ rated NBC series of the night . 
