Styx - Overture to Come Sail Away

I learned on May 7 that there's an intro to Come Sail Away. I didn't know what Lawrence Gowan and Chuck Panozzo (who joined in half way through the concert) were playing but it seemed like a good thing to capture. When it broke into Come Sail Away (which nobody seemed to see coming) there was no point in continuing to record, between 9 rows of people standing in front of me and the whole joint singing along I cut it after the opening riff so sorry, this is not the whole song. But maybe an overture you've not heard before ...