Winner at the 2016 International Latino Book Awards. Sometimes we look outside and far, losing sight of what is most important: what is inside and so close to us.

One Saturday morning, the Mouse brothers set off in search of adventure. They were very happy: the big one, the middle-sized one, and the little one. Next to the path, they saw something glittering, like a little piece of the sun. It was a little golden key. But what did it open? Could it be the key to a pirate's treasure chest? Would it open the gates of a gigantic medieval castle? The three brothers, restless and eager to find what the key opens, will embark on an adventure to solve the great mystery. The answer, however, is closer than they think...

Sometimes we look outside and far, losing sight of what is most important: what is inside and so close to us.