For those of you who were interested this is The Curse by Anges Obel. I tried it out as the part of our Nuevo/Alternative tanda. The fact that everyone danced to the one song meant that it will be repeated often.
Also to the nice people who turned up right at the end. The DJ calls it at the end of the milonga. He had called it as the last two tandas were fairly flat with not many people dancing so that was the last tango when you turned up. If our paths will cross again, across the sea, I will dance with you then!