An author spent a year and a half filming what happened as a new apartment building was built in the El Chino neighborhood of Barcelona. En Construccion focuses less on the practicalities of raising a building than the impact the project has on those who live in the neighborhood, including a teenage couple squatting in a nearby building, an illegal alien looking for work for himself and his son, and a neighborhood girl who becomes infatuated with one of the construction workers. The death of a stray cat and the discovery of a mass grave during construction also points to the tragic losses that are sometimes part and parcel of progress.