Four French “Sisters in Resistance” recall the horrors of life under the Nazis. They also recall why and how they fought it. Their activities (including plotting to free prisoners) landed them in the Ravensbruck concentration camp, where they formed a bond that would last six decades. Making their story even more remarkable, says narrator Kate Mulgrew, was that “neither Jews nor communists, they were in no danger of arrest---until they began to resist.” Adds Genevieve de Gaulle Anthonioz, one of the four (and a niece of Gen. Charles de Gaulle): “There are times when you have to say, `this is unacceptable'.”