In August 2003, Western Europe experienced a deadly heat wave. It is estimated that 15,000 people died in France from its direct effects. Applying an indirect estimation technique to the monthly number of deaths by sex, age, and place of residence for the period 1996-2003, we estimate the number of years that would have remained to those who died from the heat wave had they been spared. The paper also evaluates the role of the 'harvesting' effect of the 2003 heat wave in explaining the deficit of deaths recorded in 2004--estimated at 23,000 out of an expected total of 535,000 deaths. The harvesting effect was modest and accounted for fewer than 5,000 of the 'missing' deaths in 2004. The mortality decline in 2004 is thus due mainly to other factors. One hypothesis is that special efforts have been directed towards isolated older people as a consequence of the heat wave.