Roast beef, tongue, cold chicken, salad, sandwiches… “And the fish mayonnaise!” Elsa Einstein calls out to the girls. “Do we have enough beer in the house?” For bandmaster Dr. For Strauss it has to be Spatenbräu, for Gerhart it has to be Hauptmann Rheinwein. Elsa Einstein is proud of the celebrities who accept her no less famous husband’s invitation to the house near Caputh an der Havel. None of them expect that Albert Einstein, 50 years old, Nobel Prize winner in physics, will present an invention on this summer evening in 1929: a time machine that he calls the “Chronoplan”.