At the beginning of Nicole Krauss' debut novel Man Walks Into A Room, amnesiac protagonist Samson Greene has been found wandering in the Nevada desert. Doctors examine him, find a cherry-sized tumor in his brain, and remove it, which returns Greene to normal human function, save for the continued ignorance of what happened to him from age 12 to age 36. At this point, the author has a blank slate in her hands; she could take her story in any direction, from broad comedy to comprehensive miserablism. Krauss chooses to stop with the blank slate and reflect on that for a while. Her Samson Greene is a poignant figure: a beloved young Columbia University English professor who can't remember any of the literature he's read, and a married man who can't recall any of the gradual, mutual personal developments which led him to fall in love with his wife. He's also apparently happy with his fog, enjoying the close connection to pre-teendom—really remembering life as a child of the '70s may be the ultimate fantasy for Generation X-ers—and relishing the anonymity of crowded city streets, where even the should-be-familiar holds novelty. Eventually, and somewhat surprisingly, Man Walks Into A Room develops a plot. A Dr. Ray Malcolm asks Greene to return to the desert for a series of memory-related experiments, and Greene agrees. Krauss jumps her narrative ahead to give readers the Memento-like feeling of being as lost as the book's hero, but bit by bit, she fills in the gaps and considers the ramifications of Greene's decision to let another man tinker with his brain. Malcolm wants to examine the meaning of human empathy, figuring that shared memories might lead to close personal connections and thereby prevent wars. Meanwhile, Greene finds that the more experiences he has, and the more new memories he creates, the more unpleasantly complicated his personality becomes. The plot-heavy second half of Man Walks Into A Room doesn't always come to as much as Krauss intends, partly because her tendency toward expository dialogue muffles the naturalism that such a cerebral fantasy requires. But her gift for metaphor keeps the book's central premise fresh, as she compares Greene's predicament to being a clone, or to a man seeing himself in the mirror after a recent haircut. In the knockout epilogue, in which the point of view shifts suddenly to Greene's wife, Krauss effectively and unsettlingly communicates the tenuousness with which everyone is in touch with their identities and how they appear to others.