It's playing when they go into the main doctor's house on the island and the other guy is in there with them and he even says what it's called and who it was written by but I can't remember... It also plays when Leonardo's character flashes back to the Nazi general laying on the floor with half his face blown off.
"Symphony No.3 Passacaglia - Allegro Moderato" by Krzysztof Penderecki. A bit dark & eerie for me.
