The title of the film, set in Luxembourg in 1942, during the Nazi occupation, amalgamates the words Schacko (helmet) and chapeau claque (opera hat). The village, in which it is set, has not yet been feeling the effects of the war at this point.
The Time Machine is purchased from an antiques store by a physician from Berlin. Much of the script plays out in one room in the Berlin villa of Dr. Erasmus Beilowski. He and his well-educated friends have an intelligent discussion about the world and the future, with a view to the Time Machine. What to use it for?
In this action comedy the French boxer Jo Cavalier is charmed on the train to Berlin for the Olympics in Hitler's Germany by the little boy Simon Rosenblum who asks his autograph; when it turns out his adorable young fan is a Jewish orphan in danger of persecution, he risks his one shot at Olympic glory to save Simon and his family, helped only by a German officer-gentleman who became his friend in World War I, by an adventurous escape to Switzerland, Nazi troops on their heals and braving impossible odds in roller coaster-style.