The protagonist of the novel Caspar Hauser had a prototype - a real person who was written and talked about all over Europe. He suddenly appeared in 1828 in Nuremberg, this young stranger of about sixteen or seventeen, whose past was shrouded in mystery and whose short life was soon forcibly interrupted.
The novel begins with a description of the events in Nuremberg in the summer of 1828. Residents of the city learn that a young man of about seventeen is detained in the fortress tower, who can’t tell anything about himself, because he speaks no better than a two-year-old child, only takes bread and water from the guards and walks with great difficulty. On a piece of paper he was able to write his name: Caspar Hauser. Some suggest that this is a caveman, others - that he is just an underdeveloped peasant. However, the youth's appearance - velvety skin, white hands, wavy light brown hair - contradicts these assumptions. When a stranger found a letter from which it appears that in 1815 the boy was thrown into a poor house, where for many years he was deprived of communication with people. In the summer of 1828 he was taken out of hiding and, pointing the way to the city, left alone in the forest.
The mayor of the city, Mr. Binder, suggests that the young man is a victim of a crime. Interest in the young is growing, crowds of people come to see him. Of particular interest to him is teacher Dowmer, who sits with him for hours and, gradually teaching Caspar to understand the human language, learns something about his past. But the young man still cannot answer questions about who his parents are and who kept him in the dungeon. Master Dowmer, summarizing all his observations, publishes an article in print, especially noting the purity of the soul and heart of Caspar and making an assumption of its noble origin. The conclusions made by Dowmer alarmed some members of the district government, and the Nuremberg magistrate, led by Baron von Tucher, decides to turn to the President of the Court of Appeal, State Councilor Feuerbach, who lives in Ansbach, for advice and help. At Feuerbach’s insistence, Casper’s guardian is Daumer, who continues to discover Caspar’s world of things, colors, sounds, the world of words. The teacher never tire of repeating that Caspar is a real miracle and that his human nature is sinless.
Once a teacher throws a note at the house with a warning against possible troubles. Dowmer reports this to the police, the police to the Court of Appeal. From the district administration, instructions come to the Magistrate of Nuremberg to strengthen supervision of Caspar, since the latter may well conceal something. The more Caspar learns about the real world, the more often he dreams. Once Caspar tells Daumer that he often sees in a dream some beautiful woman, a palace and other things that excite him very much, and when he recalls them in reality, he becomes sad. He constantly thinks about this woman and is sure that she is his mother. Dowmer is trying to convince Caspar that this is just a dream, that is, something unreal and having nothing to do with reality. For the first time, Caspar does not believe in a teacher, and this makes his sadness even more intensified.
Dowmer and Binder write a letter to Feuerbach, where they talk about the young man's dreams and his feelings. In response, Feuerbach advises Caspar to ride and ride more often. At the next meeting, Feuerbach gives the young man an excellent notebook in which he begins to keep a diary. The attention of society to Caspar does not wane; he is often invited to visit noble families. One day, Dowmer, accompanying Caspar, meets an important foreigner named Stanhope, who manages to raise doubt in the soul of the guardian about his ward. Dowmer after this conversation begins to closely monitor Caspar, trying to convict him of insincerity or in a lie. Especially unpleasant to the guardian is Caspar's categorical refusal to read him diary entries. Caspar does not leave a feeling of anxiety, he is in deep thought. Once, while walking in the garden near the house, he sees a stranger with his face covered in cloth. A stranger approaches Caspar and stabs him in the head. The police did not find the criminal who injured Caspar.
Advisor Feuerbach, having gathered all the facts known to him, writes a memorandum to the king, where he claims that Caspar Hauser is the offspring of some noble family and that his child was removed from the palace of the parents so that someone else would be approved as a legacy. In this straightforward revelation, Feuerbach directly points to a particular dynasty and some other details. In a reply sent from the king’s office, Feuerbach is ordered to remain silent until the circumstances are fully clarified. Daumer, frightened by the assassination attempt on Caspar, is seeking permission to change the young man's place of residence.
Caspar's guardian is Madame Behold. Eccentric and overly energetic, she is trying to seduce a young man. When the frightened Caspar evades her caresses, she accuses him of tactless behavior towards her daughter. Exhausted Caspar wants to leave this house. Mr. von Tucher, having assessed the situation and regretted Caspar, agrees to become his next guardian. Silence and boredom reign in the house of Tucher, the guardian, being a strict and unhappy man, rarely communicates with Caspar. Caspar is sad, his soul is looking for a more sincere affection, he is again tormented by bad forebodings.
Once a young man is brought a letter, and with it a gift in the form of a ring with a diamond. The author of the letter, Lord Henry Stanhope, soon arrives in the city on his own and visits Caspar. Stanhope is surprised at Caspar's cordiality and willingness to conduct long and frank conversations with him. Caspar is glad that Stanhope promises to take him with him and show the world. He also promises to take Caspar to a distant land to his mother. Now they often see each other, walk together, talk. Stanhope submits a petition to the magistrate for custody of Caspar. In response, he was asked to provide evidence of his well-being. The city authorities constantly monitor him, Feuerbach orders to inquire about him. The Lord’s bright, but faulty past is becoming known: he was a mediator in dark affairs, an experienced catcher of human souls. Having not received permission for guardianship, Stanhope leaves, promising Caspar to return. He had already managed to plunge into the soul of the young man the hope of his future greatness.
After a while, Stanhope arrives in Ansbach and masterfully disposes of both urban society and Feuerbach. He receives a letter instructing him to destroy a document, having previously taken a copy from it. Stanhope begins to worry when a police lieutenant Kinkel offers him his services and acts as if he knows everything about Stanhope's secret mission. The Lord manages to convince Feuerbach to transport Caspar from Nuremberg to Ansbach. The young man began to live in the house of the teacher of Quantum. He still meets with Stanhope, but he is not always easy and pleasant with him: sometimes Caspar feels some fear in his presence. A sense of danger increases in him both when Kinkel appears and during the moralizing of the aggressively inclined Quantum, Feuerbach, who has not lost interest in Caspar, publishes a pamphlet about him that directly speaks about the criminal nature of Caspar's story. He plans to organize a secret trip in order to find the culprit of this crime. Kinkel, playing a double game, skillfully disposes of an adviser and receives orders to accompany him on this trip.
Caspar is now often in the house of Frau von Imhof, a good friend of Feuerbach. After some time, he met there with Clara Kannavurf, a young, very beautiful woman with a dramatic fate. In the absence of Kinkel, a new overseer should follow Caspar. The soldier performs his functions quite tactfully, imbued with sympathy for the young man. This is facilitated by the fact that he read the Feuerbach brochure. When Caspar asks him to find Countess Stephanie somewhere in another principality and give her a letter, the soldier, without hesitation, agrees. Meanwhile, in Ansbach comes a message about the sudden death of Feuerbach. The adviser's daughter is confident that her father was poisoned and that this is directly related to his investigation. Stanhope, too, will never return to Caspar again: he committed suicide somewhere in a foreign land. Clara von Kannavurf’s attempts to somehow cheer Caspar to no avail. Feeling that she is falling in love with a young man and that happiness with him is impossible, she leaves.
After some time, an unfamiliar gentleman approaches Caspar at the courthouse and tells him that he was sent by his mother and calls him “my prince”. The stranger says that tomorrow he will wait for the young man in the palace garden with the crew and will show him a sign from his mother, proving that he is indeed the countess's messenger. A dream full of anxieties and symbols, which Caspar sees at night, cannot shake his decision. At the appointed time, he comes to the garden, where they show him a bag, saying that there is a sign from his mother. While Caspar unties this pouch, they stab him in the chest with a knife. The mortally wounded Caspar lives on for several more days, but he cannot be saved.
