Steppenwolf opens with a preface by a young businessman, who introduces a sheaf of notes left behind by a lodger in his attic rooms several years before. This young man, the landlady’s nephew, describes the eccentric lodger, Harry Haller, who called himself a Steppenwolf, meaning in German a wolf of the steppes, or plains. The narrator finds this an odd but apt description of the shy, lonely wanderer who revealed little about himself but left a haunting memory.
The preface recounts Harry’s arrival and the narrator’s several encounters with him- on the stairs, at a concert and an art lecture, and in a tavern. He has decided to publish Harry Haller’s records although he can’t say whether the experiences it relates were real or fictitious. Haller’s records, subtitled For Madmen Only, begin with a walk in the dusk after a boring day. The walk takes Harry into an imaginary world by way of a flickering sign, an appearing and disappearing little door in a church wall, and a peddler with a placard advertising, Magic Theater- Entrance Not For Everybody.
The peddler hands Harry a pamphlet and vanishes. in his room again, Harry examines the pamphlet. It is called Treatise on the Steppenwolf and is a second portrait of Harry, a psychological one this time. It analyzes Harry as inwardly half man and half wolf, two selves in constant conflict. It describes Harry’s struggle to be himself, which has resulted only in greater loneliness. It explains to Harry the role of the Steppenwolves- the artists and intellectuals- in middle-class society, and the geniuses who break free and become Immortals.
It tells Harry that his wolf is an oversimplification, that he has not two but hundreds of selves. Some day he may see himself in one of the Immortals’ magic mirrors, or find in one of their magic theaters what he needs to free his soul. Finally the anonymous authors bid Harry good-bye and cheer him on his path toward becoming an Immortal. Harry, again in the first person, compares what the Treatise says of him with a poem he has written about the wolf. He finds them both true and unbearable.
He recalls the successive crises in his life, the despair, and the new self-knowledge he has gained each time at the cost of increased loneliness. He will not go through this again. He will end it, commit suicide. But first, the Magic Theater. After nights of search he finds the peddler, who directs him to a seedy tavern. Here he meets the bar girl Hermine, who introduces him to the prostitute Maria and the jazz musician Pablo. With Hermine as guide, Harry learns to dance and to enjoy sex and the night life of the city.
He joins the revelers at a masked ball. Pablo, as master of ceremonies, invites Harry into the Magic Theater. Here, in a series of dreamlike adventures, Harry fights a war against automobiles, makes love to all the women he has ever loved, commits an imaginary murder, and prepares to be executed. Instead, he is condemned to go on living. Pablo rebukes him for messing up his magic with reality. Harry acknowledges that he will go on trying to face his inner self, and perhaps learn to do better next time.