A word from the designer:" In the summer of 1997, I saw two mackerels that had somehow managed to get into the sardine tank at the aquarium. Watching these two fish unable to blend in with the shoal of sardines made me wonder if they were on a journey of self-discovery. What sort of adventure will they have? Imagining this led to the conception of six cast puzzles based on oceanographic subjects. Subject: Sharks A shark playing with a fossilized shark. Once you have helped it escape, put it back again." Yamamoto 2008.