Anybody ever discover hidden or surprise art? I have one cool example. I'ts not quite the same as removing the stats from a stat cover to reveal an actual hand drawn Kirby FF cover (which happened), but cool nevertheless.
I picked up this Starlin painting, the Infinity War promotional poster. When I received it, it reaked of smoke, cigarettes and looked like this. There was no way Starlin painted this piece with such a muted palette.
Had it professionally cleaned (no varnishing) and voilà, it was like a completely different piece. The dull colors were replaced by a deeply colored, vibrant painting. A photo just doesn't do it justice. Now one of my favorite pieces.