On the basis of the fate of Mathias Thesen, a trade unionist and KPD member of parliament who spent time in concentration camps and penitentiaries from 1933 to the end of 1944, I use a day of action to convey what resistance in a totalitarian state means in very concrete terms. Thesen was my mother's favorite uncle, and from him I learned personal stories as a child that have decisively shaped my life as a citizen, democrat and artist. With the help of a film documentary about Stolpersteine, a contemporary novel set in a concentration camp with my great-uncle as the main character, a contemporary monograph about his life and, last but not least, with the help of a duplicate of a Stolperstein made for me by Gunter Demnig, I can vividly, multimedia-based and very concretely relive the conditions at that time under which resistance was dangerous but possible.