A research worker Robespier Galabov (Yakovlev) lives with his family in a small communal flat with shared kitchen and dreams about a self-contained home. Galabov meet Rangel Lelin (Gospodinov), the well-known amidst the localities as the past-master, when he realized that the new municipal apartment they apply for won't be ready in the next decade. The Past-Master promises to build the private house in a month. After starting the construction, Rangel Lelin constantly blackmail Galabov for more money through treat of "putting the hat". Finally the house was built but the inauguration become gloomy. It turns out that the chimney of the fireplace doesn't work properly. After days of luckless attempts to solve the problem the past-master's brother come into sight. Knowing the Lelin's tricks he find a hat built in the chimney.