It all begins when Grandpa Yólotl disappears. Matías, Claudio, Pato, Katy and loyal dog Duke uncover signs that will lead them to a great adventure, facing unimaginable creatures, astonishing characters – that once belonged to an ancient civilization, and a couple of rogue treasure hunters. The promise of their grandfather is the force that will guide these heroes, ready for anything, provided they always stay together and discover the secret of the jade medallion.

一场华丽的化妆舞会，青春小正太Lucas却吓跑了所有朋友。因为短短几秒钟，乖巧懂事的他变成了一个长着翅膀的超级大怪物！而他自己也被吓得张皇失措。气愤父亲隐瞒家族身世之余，Lucas偷拿到一张神秘地图，决心靠自己找到父亲偶然提及过的真正家乡——怪物岛。当他历经艰险完成远航，眼前的所有景象都足以让他目瞪口呆。可没想到，这场寻根之旅，让他找回亲人的同时，也让他自己和岛中居民陷入了一场生死大考验……