Continuity mistake: When Peter and Carl are talking outside while Peter is drunk, Carl goes to turn away. Suddenly, the colours of his hat switch around, the orange and grey portions swapping places. (00:14:33)
Continuity mistake: During the AA meetings, Dr. Hartman's, Bruce's, and Tom's buttons switch sides between shots.





Chosen answer: It's a real song called "Elvira". Originally by Dallas Fraizer in '66, however, this version seems to be the Oak Ridge Boys cover version. However, the mega lesbians skip the verse and just sing the chorus after the opening line.
Bishop73