A production of eikon with Cross Media and Conradfilm in co-production with the lead MDR, ARD Degeto, BR and SWR for Das Erste. The production is supported by the Mitteldeutsche Medienförderung (MDM) and the FilmFernsehFonds Bayern (FFF Bayern).

Abandoned as a child in the monastery of Nimbschen (Saxony), Katharina von Bora lives the life destined for her until, in her early 20s, she comes into contact with a completely new world of thought through the writings of Martin Luther, which are secretly circulated there. If what Luther wrote was true, that man's relationship with God was determined by God alone and did not depend on the good works of the faithful - what was keeping her behind the monastery walls? Katharina ventures into the unknown and flees with some of her fellow sisters in search of a new life. When the young woman, without legal status, without income and disowned by her family, finds lodgings in the house of Lucas Cranach in Wittenberg, she meets Martin Luther in person.

Katharina experiences him as a completely different person from the "here-I-stand-and-can't-do-anything-else" fighter: vulnerable, sick, full of doubt, and eager to work to the point of exhaustion. She falls in love with the banned reformer who is inspired by his mission. As his wife, she begins a new life, becoming a respected landlady, Luther's equal in conversation, and the mother of their children. But with the early death of their daughter, she and Luther fall into a deep mourning, in which old fears and doubts catch up with the couple and shut them off from each other. Only when Katharina gains new courage to face life does she find her way back into it.

Directed by Julia von Heinz ("Hannas Reise", "Ich bin dann mal weg"), the film stars Karoline Schuch (as Katharina von Bora) and Devid Striesow (as Martin Luther) as well as Ludwig Trepte (as Philipp Melanchthon), Martin Ontropp (as Lucas Cranach), Claudia Messner (as Barbara Cranach) and Mala Emde (as Ave von Schönfeld) and many others in front of Daniela Knapp's camera. The screenplay was written by Christian Schnalke ("Die Himmelsleiter"). Katharina Luther" was filmed in Thuringia, Saxony-Anhalt and Bavaria.