Lucia is a single parent to a child with Asperger's. She has a minimum wage job and a very difficult relationship with her mother, but she thinks she can deal with everything on her own. One day she receives an urgent call from the school: her son hit his head and she needs to pick him up.

As if shedding his skin, Jorge celebrates a new birthday, in the midst of an internal struggle that will turn the evening into his most terrible nightmare.

The discovery of a mysterious letter turns the archaeological remains of Santa Fe La Vieja into a playground for adventure. The mission Mina's grandfather entrusts his granddaughter with will unravel a web of intrigue that will reveal stories of a city from bygone times. A city built on the shores of a freshwater sea that still has secrets to tell.

Even the noblest intentions succumb to human nature.