Four volunteers participating in a community mediation pilot project in Longueuil are asked to implement this new approach to conflict resolution. A disagreement has caused a rift between neighbours, and the mediators attempt to reconcile the diametrically opposed viewpoints of the two parties involved. The camera takes us to the core of the mediation process, where tempers are ready to flare. By probing this intense and demanding procedure, Story of a Mediation explores the challenges of communicating in situations of conflict and gives us a captivating look at the generosity of people willing to invest their time and energy to help their fellow citizens enjoy more harmonious relations.