This film is based on the true story of the Catalan lawyer and engineer Narcís Monturiol i Estarriol (Figueres 1819 - Barcelona 1885) who invented the submarine.

A family spends an afternoon of tension, silences and secrets with the only expectation of knowing what they are hiding from each other.

Elena, 7 years old, is going for the first time to her grandmother's after years without seeing her. Grandma, old and touched by Alzheimer's, entrusted Elena with the complex task of bringing the stars, those, she says, are hidden around the house. The visit becomes an adventure to bring those stars to make real the grandma's last wish.