The Grotto of Dancing Deer

A group of archaeologists studies rock drawings found in a cave. At the end of all the work, when they began packing up their tents, one of the researchers, Boyd, discovers a hidden grotto painted by an unknown artist two centuries earlier—so indicated by hydrocarbon analysis conducted later from paint samples and fingerprints taken in the FBI laboratory. But a chain of coincidences leads Boyd to think that this artist is in his own group. And that artist is twenty thousand years old…

Hugo Award laureate (1981).