Dr. Max Holst, a renowned neurosurgeon, is the main character in this story. One day, an intense little man named Steinmetz shows up and claims to have the ability to create objects out of thin air using only his mind. Dr. Holst initially believes him but eventually finds out that Steinmetz is a mental patient being held at a ward for the mentally ill.
Steinmetz manages to escape from the ward and shows Dr. Holst his mansion filled with expensive paintings and sculptures. He proves that he can actually materialise objects by creating them out of thin air. Steinmetz's abilities continue to evolve as he progresses from being able to create objects to living creatures. His ultimate goal is to create a human being.
Steinmetz tells Dr. Holst that if he will perform a certain brain operation on him, he will be able to achieve his goal. However, Dr. Holst is too scared by the whole thing and refuses to agree to the operation. As a result, Steinmetz begins to manipulate Dr. Holst's life to pressure him into performing the operation.
By then, Steinmetz has become able to create a temporary human being. He hopes that this creation will be able to perform the operation on him. To make sure this happens, he creates a doppelganger of Dr. Holst and sends it to take over Dr. Holst's life. This doppelganger starts causing chaos in Dr. Holst's professional and personal life.
Finally, Dr. Holst decides to fight back. The ending of the story is both unexpected and satisfying.