Renata seeks refuge in the house of Virginia, her sister. Virginia lives a quiet life with her son Lucio in a provincial city and the only thing that seems to worry her are the ants that have invaded her home. Renata has nowhere to go. Virginia wants to help her and receives her; But the days pass and the drama of daily life begins to reveal the link between them, the pain of recognizing and rediscovering each other in a past that returns and takes strange forms.
Damián, an 11-year-old boy who is separated from his violent family, is taken to live in a children's home by state intervention. Accompanied by Leandro, a social worker with a personal story similar to his, Damián will have to accept that his previous life is behind him and will not return, but it is still possible to build a new beginning where there is room to not feel so alone.
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.
Ariel is a middle-class young man, a father of a family, who surprisingly loses his job in the context of a wave of layoffs. Altered and hiding from his family what happened, he escapes his father-in-law's birthday to go to a nightclub, where an old acquaintance offers to be part of a narco business. Ariel accepts, trusting that his participation will be limited, but things go out of control.
One summer afternoon, on the banks of a river, a boy and a girl are starting to get to know each other. The landscape and the distance are the scene of a possible beginning.
Trombone is not a classic documentary, in the same way that Trombonanza is not a classic experience in the world of trombone. It is full of moving stories, secret tributes, huge celebrations and above all music.