The action takes place in the 20th century in Danzig. The narration is conducted on behalf of Oskar Matzerath, a patient of the special medical institution, a person whose growth stopped at the age of three and who never has parted with a tin drum, confiding to it all the secrets, describing to it everything he sees around him. Th orderly named Bruno Munsterberg brings him a pack of blank paper, and he starts his own biography and that of his family.
First of all the narrator describes the grandmother, Anna Bronski, a peasant, who once in October of 1899 saved form gendarmes his grandfather Joseph Koljaiczek, having tucked him under her numerous wide skirts. Under these skirts on that memorable day his mother Agnes was conceived. That same night Anna and Joseph married, and grandmother’s brother Vincent drove them in the central city of the province: Koljaiczek was hiding from the authorities as an arsonist. There he settled as a raftsman named Joseph Vranken, who had drowned some time ago, and lived until 1913 so until the police got to his trail. In that year he had to overtake a raft to Kiev, which sailed in tow "Radauna".
On this ship happened to be a former master of sawmill where Koljaiczek worked, who gave him up to the police. But Koljaiczek did not want to go to the police and upon arrival at the home port jumped into the water hoping to get to a nearby pier, where just launched the ship under the name "Columbus". However, on the way to the "Columbus" he had to dive under the raft which was too long, where he found his death. As his body was not found, there were rumors that he managed to escape and he sailed to America, where he became a millionaire .
A year later his grandmother married the elder brother of her late husband, Gregor Koljaiczek. As he drank away all that was earned on a powder mill, the grandmother had to open a grocery store. In 1917 Gregor died from the flu, and in his room Jan Bronski, grandmother's brother's son has settled, who was going to serve at the main post office of Danzig. He and his cousin Agnes really liked each other, but never married, and in 1923, Agnes married Alfred Matzerath, who she met in the hospital, where she worked as a nurse. However, the delicate relationship between Jan and Agnes did not stop - Oskar repeatedly emphasizes that is more inclined to consider his father Jan, than Matzerath. Jan himself soon married Kashubian girl Hedwig, and had son Stefan and daughter Marga. After the conclusion of a peace treaty, when the area around the Vistula River was declared a Free City of Danzig within the boundaries of Poland and received a free port, Jan went to serve in the Polish post office and received Polish citizenship. The Matzeraths engaged in trade.
Soon Oscar was born. Endowed with an acute perception, he always remembered his father's words: "Someday the shop will be his" and mother’s: "When little Oskar is three years old, he will get a tin drum." His first impression was the butterfly, beating in a burning light bulb. He seemed to be drumming and the narrator called him Oskar’s mentor.
The idea of getting the shop caused a feeling of protest but he liked mother’s offer. Immediately realizing that he was destined to be misunderstood by his own parents, he did not want to live, and only a promise of a drum reconciled him with reality. First of all the narrator did not want to grow as it was for him the only possibility to save the drum. When Matzerath tried to grab the drum, the boy’s cry broke the glass of a floor clock. When for his fourth birthday they tried to replaced the drum by other toys, he crushed all the lights in the chandelier.
Oscar was six years old and his mother tried to define him in school named after Pestalozzi, although from the point of view of others, he still did not really know how to speak and was very undeveloped. At first the boy liked the teacher named Miss Shpollenhauer, because successfully drummed a song she asked him for, but then she decided to remove the drum in the cabinet. On the first attempt to pull out the drum Oskar only scratched her glasses, on the second his voice broke all the glass panes, and when she tried to hit him with a stick on his hands, he broke her glasses, scratching her face. Thus ended for Oscar studying at school, but he in no matter what wanted to learn to read. However, none of the adults cared for the underdeveloped freak and only his mother's childless friend Gretchen Scheffler agreed to teach him to read and write.
Selection of books in her house was very limited so they read "Elective Affinities" by Goethe and weighty volume "Rasputin and women." The study was easy but he was forced to hide his achievements from adults, and it was very difficult for him and insulting.
At first Oscar’s world was limited to the attic from which nearby yards were seen, but once the kids fed him with "soup" of pounded brick, live frogs and urine, after which he began to prefer long walks, often hand in hand with his mother. On Thursdays, the mother took Oskar with her to the city where they invariably attended Sigismund Markus’s toy store to buy another drum. Then she left Oskar with Marcus and went to the cheap rooming house that Jan Bronski specially rented for meetings with her. One day, the boy ran out of the store to try his voice at the City Theatre, and when he returned, he found Marcus on his knees in front of his mother: he persuaded her to flee with him to London, but she refused because of Bronski. Alluding to the coming power of the Nazis, Marcus, among other things, said that he was baptized. However, this did not help him - during one of the riots, not to fall into the hands of the rioters, he was forced to commit suicide.
In 1934 the boy was taken to the circus, where he met a dwarf named Bebr, who said him: "Try always to sit among those in the stands, and never stand in front of them. Young people like us would find a place even on the crowded stage. And if not on it, then under it, but never in front of it". Oskar always remembered the words of an old friend, and when one day in August 1935, Matzerath, joined the Nazi party, he went to some demonstration, Oskar, hiding under the bleachers, spoiled all the procession, knocking stormtroopers with waltzes and other dance rhythms on his drum.
In winter 1936/37 Oscar pretended to be an adversary: hiding in front of some expensive store, he carved out a small hole in the window with his voice so the buyer could take his favorite thing. Thus Jan Bronski became the owner of an expensive ruby necklace which he presented his beloved Agnes.
Shortly after visiting the church on Good Friday, the Matzeraths together with Jan went for a walk along the beach, where they became witnesses of how a man caught eels on the horse's head. It impressed Oskar’s mother so much that she stayed in shock for a long time, and then began to eat fish in large quantities. It ended with his mother’s death in a city hospital from "jaundice and fish toxicity." At the cemetery Alexander Scheffler and musician Maine roughly drove Marcus away, who came to say goodbye to the deceased. At the local cemetery gates crazy Leo Fool as a sign of condolence shook Marcus's hand. Later, on the other funeral, he would refuse to shake hands with musician Maine, who entered into storm troopers.
On that day, when Leo Fool refused to shake hands with attack aircraft, Oskar’s friend Herbert Truchinski was buried. He had long worked as a waiter in the port tavern, but resigned from there got the place of a caretaker to the museum - to protect a Galion figure, which was believed to bring bad luck. Oskar served Herbert as a sort of talisman, but one day, when Oskar was not allowed in the museum, Herbert died a horrible death. Worried by that memory, Oskar is beating particularly strong into the drum, and the orderly Bruno asks him to drum softly.
