A Jewish tannery worker, Nahum Beychik, invents a machine that makes hard work easier in leather tanning. A private entrepreneur, former kulak Lopatin, tries to buy the invention and use it for his own selfish interests. Having met with a decisive refusal from Nahum Beychik, the kulak exploits the anti-Semitic sentiments of the backward part of the workers and, with the help of his accomplices, hooligans and truants, tries to kill the inventor.