On one hand, about 150 years ago, in his dusty laboratory, Cosinus, an old and original professor of chemistry, looks for the good formula to bring to a successful conclusion an experiment. On the other hand, nowadays, in a specialized french school, students are manufacturing tablets for the bio-processing industry. A film to understand how the efforts and failures of the old alchemists of former days were able to end in the elaboration and progress of the modern science, mostly for the manufacturing of tablets.