The story takes place in Prague in the 1930s. An old trickster watchmaker named Sakař fakes an illness to get into the hospital. A young doctor from Bulovka finds him on the street and admits him to the hospital. Sakař is an excellent specialist, he takes care of everyone's watches, but at a certain point his desire for freedom wins out and he runs away from the hospital with a rare piece of old watch, which unfortunately belongs to the headmistress. A problem arises for the doctor, his position and existence are threatened...