No sooner does Martin Harris arrive in Paris, on leave from Yale to study botanical genetics at a French institute, than he gets into an auto accident that puts him in a coma for several days. But when he awakens, ID-less, and shows up at his rented flat, his wife doesn’t recognize him — and a man calling himself Martin Harris angrily ejects him from the building. Thus begins French author Didier van Cauwelaert’s convincing little nightmare, a Twilight Zone-ish yarn that tests poor Martin as well as the very notion of how human identity is shaped. The scientific gloss helps cover some of the plot’s surface implausibilities. In fact, the premise is so intriguing, and so engagingly developed, that you won’t mind that Martin never bothers to, say, seek out the U.S. embassy for help.