In 79 AD, the eruption of Mount Vesuvius buried the city and inhabitants of Pompeii under volcanic debris and preserved—until excavations in 1909—a vast fresco painted a century and a half earlier in a suburban villa. Populated by twenty-nine life-size figures against a vivid red background, this decoration, as famous as it is enigmatic, has given rise to several interpretations, which this film seeks to clarify with the help of documentary evidence.