Twelve-year-old Ramón receives a bicycle from Mario, an old amateur cyclist who built the bicycle in his workshop using pieces from different models. With his new bike, Ramón runs errands for a steroid dealer, crossing a city in the throes of transformation. By a whim of destiny, the bicycle ends up with Julia, a 20-year-old girl who left her village to live in the city, where she finds work as a bicycle courier to pay for her Chinese studies. And so Julia confronts the aggressiveness of the daily traffic and the hard conditions of precarious employment. The bicycle finally ends up with Aurora, an elderly lady from the old sailors’ quarters, whose house will soon be demolished to make way for an avenue of brand new houses. Aurora starts to cycle again and decides to embark on a search for the original owner.