The titular Marie-Louise is a young French lass who is evacuated to Switzerland when her country is overrun by the Nazis. Suffering a nervous breakdown, she is given comfort and shelter by a wealthy family. Unfortunately, living in the lap of luxury makes Marie-Louise hesitant to return home to her mother and war torn home. Eventually the girl comes to her senses, but it isn't easy.

Glacier pilot Hermann Geiger flies over a four-thousand-meter peak in the Valais Alps and observes a glacier collapse. The next day, three rope teams climb through this glacier to Dent Blanche. However, Dr. Gruber, accompanied by his wife, a young engineer named Gisler with his girlfriend Monica, two young men named Charly and Roby, mountain guide Perren, and the athletic Englishman Puckle get caught in a storm. Due to the weather conditions, Gruber slips and drags the other participants down with him. His wife, who had stayed behind in a hut, alerts the mountain rescue service. The storm initially prevents glacier pilot Geiger from taking action, but he then risks a breakneck landing to rescue the group.

A policeman is not convinced that the prime suspect in a murder case is realty guilty and so decides to reinvestigate the case, despite the lack of co-operation from locals.