This introduction was all part of one song, "Duel Duet" when featured on the vinyl soundtrack.  However, when it was transfered to the CD soundtrack, it was not included as part of the song "Duel Duet."  Instead, it was tagged onto the end of the previous song, "Breaking Out."

Audience Member: Ah, it's a crazy night!
Brad: Seducer!
Farley: And who are you, sir?
Brad: Your twin brother and your accuser!
Janet: Brad!
Cosmo: Arrest that man, he's commited to our care!
Janet:  I never never signed your contract.  He's not going anywhere.
Oliver: To revenge your twin, you tried to abuse her.
Farley: A rediculous accusation, you've forced me to refuse her.
Brad: Then why did you choose her?
Farley: Because of you, sir.