Luigi Tagrana is an outcast: homeless, jobless, to live he collects worms in the ditches of Milan (hence his nickname: Vermisat), to sell them as bait. Vermisat enters and exits the hospitals and from prison, where however it is a number, more than a person. Only the meeting with a prostitute, Maria, alone like him, seems to soothe the solitude of both. However, forced to hunt worms at night out of fear of the peasants, takes pneumonia and is forced to umpteenth hospitalization. He does not trust the hospital's medicines, he does not take them, and he quits, without the doctors making any resistance: he ends up in the hands of a charlatan, the Medicon, who not only provides him with fake medicines in exchange for blood, but Mary also blows him. Once again alone, he moves away from Milan, ending up again in a nursing home.