If the game freezes, just click inside it (games can get unresponsive if you click elsewhere on the page).
You are a small piranha lost in the big ocean. You are known as the Hero. There is a long journey for the Hero, and it must finish all the levels to find its family... but that will not be so easy. In its road, the Hero will need to eat in order to grow up, but at the same time it has to pay attention to not be eaten by bigger or stronger aquatic animals.