Peter Märthesheimer, born July 9, 1937, in Kiel, studied economic sciences and sociology in Frankfurt am Main and then worked from 1964 to 1974 as contributing editor/producer and as a dramaturge for WDR in Cologne where he was in charge of a number of seminal TV movies, including Tom Toelle’s and Wolfgang Menge’s "Das Millionenspiel" ("The Millions Game", 1970), Rainer Werner Fassbinder’s "Welt am Draht" ("World on a Wire", 1973) and "Martha" (1974), as well as Bernhard Sinkel’s "Lina Braake" (1975). Together with Menge, he also developed the ecological drama "Smog" and the TV series "Ein Herz und eine Seele" that later established a cult following.

After his successful term at WDR, Märthesheimer worked for Munich’s Bavaria Film for seven years. In 1979, he made his debut as a screenplay writer in collaboration with Pia Fröhlich for Fassbinder’s film "Die Ehe der Maria Braun" ("The Marriage of Maria Braun"). During the following years, Märthesheimer wrote and produced, respectively, Fassbinder’s films "Berlin: Alexanderplatz" (1980), "Lola" (1981, co-authored by Märthesheimer and Fröhlich), and "Die Sehnsucht der Veronika Voss" ("Veronika Voss", 1982, co-authored by Fröhlich and Fassbinder).

In 1994, Peter Märthesheimer became a professor for screenplay writing and dramaturgy at Filmakademie Baden-Württemberg. Märthesheimer’s last works include the screenplays to the TV crime series "Bloch" (2002 to 2005), starring Dieter Pfaff in the leading role.

On June 18, 2004, Peter Märthesheimer died suddenly and unexpectedly during a general meeting of Filmakademie in Berlin.

Two years later, Margarethe von Trotta made a film version of the novel "Ich bin die Andere" ("I Am the Other Woman") that Märthesheimer had written in 2000. The novel was adapted for the screen by his longtime companion Pia Fröhlich.