Weird soundtrack question

Last night, I was flipping around channels and noticed a bizarre coincidence. Layer Cake and Hannibal (each on a Cinemax channel at the time) seemed to be playing the same song. It sounded vaguely opera-ish. I compared the two soundtrack listings and there are no matches. Based on the fact that it had male and female vocals, I'm guessing it was the 'Vide Core Meum' on Hannibal. I'm going to see if I can find an audio file to listen to; but maybe someone here recognized it in Layer Cake?