I was in a café in Barcelona having a couple of drinks with my friend. I went to the restroom, and while I was in the booth all the lights suddenly went out. I found the latch by touch, and tried to get out by pushing the door, but it was stuck. I started to feel a bit uneasy, being stuck in the darkness. After a while the lights went back on, and I noticed there was a sliding door in the booth! I had not taken any notice of the door while going in because everything went smoothly.