Clarisse Norman is a shy girl who lives in the New Hampshire woods, training to become a psychoanalyst. During a trip to the northern forests, she kills her boyfriend for no apparent reason. After a trial finds her to be schizophrenic, she is sent to an asylum. Why is she obsessing with her own drawings? Why is shy studying an 18th-century alchemist, chased away from Europe for his deranged theories? And why is there a door that seems to give onto a sheer void, in the middle of the forest? Martin Mystère finds out that the veil dividing a rational mind from a crazed one is far thinner than you can imagine!