The Counterfeit Man is a collection of science fiction short stories by American writer Alan E. Nourse, published in 1963 by David McKay. Several of the stories have a medical or psychological theme. Contents "The Counterfeit Man". The medical officer of an exploratory spaceship returning from Ganymede determines the crew has been infiltrated by at least one highly malicious shapeshifting alien. He attempts to force the intruders, who can almost perfectly mimic human physiology down to the cellular level, to betray themselves. Succeeding with one, he ejects it into space, gaining the cooperation of the expedition commander. Upon arrival at Earth, the doctor sabotages the ship to temporarily strand it in orbit, going ahead in a shuttle - with proof in hand - to order a quarantine. When the ship lands, the entire crew is however accounted for; the incredulous doctor storms back into the ship to search it himself, only to be ambushed and killed by the remaining alien, who has taken on his own guise and who, emerging, heads into the surrounding city. This story was adapted as the second episode of the BBC television series Out of the Unknown. "The Canvas Bag" - A drifter with only a vague recall of his own past stops in a town and falls in love, which prompts him toward introspection. Examining his rather fuzzy memories, he realizes - to his shock - that he is over 150 years old. Having cursed his mother and his home, he has been punished with eternal homelessness, saddled with immortality, forgetfulness, and an irresistible thousand-year compulsion to wander the Earth. The girl he loved chases him down at the bus stop at the last minute, choosing to wander with him. "An Ounce of Cure" - a short, absurdist satirical piece on Nourse's own medical profession: a middle-aged man goes to his doctor seeking treatment of his foot pain, but instead becomes trapped in a maelstrom of arcane diagnostic procedures and endless referrals to increasingly ridiculous specialists. Eventually the patient gives up on conventional medicine and goes to a beturbaned Eastern mystic instead. "The Dark Door" - a former psychological experimenter, trapped in deeply paranoid persecution fantasies, appeals to his former mentor for help. The mentor, operating on a sinister hidden agenda, instead imprisons him in a machine resembling an early conception of a VR rig, subjecting him to a series of psychotic delusions. The