Adolescent crisis as it is manifested today in the poor suburbs is often attributed to an “ illness of ideality ”. The author shows that it is not so much a lack as an excess of material ideals that prevents the adolescent from adhering to the universal values that would facilitate his integration. To show how evolution is possible, he analyses the film La promesse (“ The Promise ”), by the Dardenne brothers, wherein one can follow step by step this evolution in the process of conversion in the widest sense and analyze the important role played by reference to the maternal imago.