Surely nothing would have happened if a teenager had not been killed on that winter in an inner city of the Parisian suburbs. Rumour has it that the police was responsable. It started with an altercation between some policemen and some youngsters, and then things got out of hand.
Nothing would have happened either if the mother of the murdered teenager (Alvaro) had not set about undertaking a hopeless struggle - breaking the conspiracy of the silence in her community, i.e. the community Portuguese settled in France. The community is rather reserved and withdrawn, and does not want to hit the headlines.