This collection includes two novellas that lead the reader through the darkest and most unsettling corridors of the human psyche. “The Abyss” at first looks like an ordinary evening walk of a love-struck student and his companion, but a chance encounter with a group of vagrants suddenly tears away the veneer of decency, releasing an ancient, animal darkness hidden beneath the fragile shell of civilization. “The Thought” makes the reader a witness to the diabolically intricate experiment of Dr. Kerzhentsev: he goes to commit murder and tries to evade punishment by pretending insanity before the investigators—until he himself can no longer tell where the line between pretense and reality lies.