Tim Fehlbaum, born 1982 in Basel, Switzerland, began studying directing at the Munich University of Television and Film (HFF) in 2002, successfully graduating seven years later. During his time at the HFF, he made several short films, including the thriller "Für Julian," which won the main prize at the Shocking Shorts Awards in 2004. He also directed music videos (such as for the Munich-based band "Blumentopf") and acted as cinematographer on other directors' films, such as Severin Winzenburg's documentary "My American Cousin" (2008).  

Fehlbaum's directorial effort "Am Flaucher," a low-budget zombie short, was shown at the 2006 Hof Film Festival, where it caught the attention of Munich producer Thomas Wöbke. Thrilled by the film's atmosphere and style, he produced Fehlbaum's first feature-length film: the apocalyptic thriller "Hell," starring Lars Eidinger and Hannah Herzsprung, won the Förderpreis Deutscher Film in the directing category at the 2011 Munich Film Festival and was screened at the Locarno International Film Festival a short time later. In late summer 2011, "Hell" was released in German cinemas.  

At the 2012 German Film Awards, "Hell" won the award for Best Music (Lorenz Dangel) and was nominated in five other categories (feature film, production design, costume design, make-up design, sound design). One day earlier, Fehlbaum had received the New Faces Award for Best Debut Feature.  

Also in 2012, Fehlbaum was director of photography on the short documentary "Doppelmord" ("Double Murder"), a student film directed by Korinna Krauss at the HFF. His own short feature film "Flicker" (2016) was also a HFF production.  

Fehlbaum's second feature film premiered in the program of the Berlinale 2021: the apocalyptic thriller "Tides" is about an astronaut who returns to a completely destroyed earth after a long space mission. At the Bavarian Film Awards 2021, Fehlbaum was honored with the Best Director award for "Tides." At the German Film Awards 2021, the film was nominated in six technical categories and won four of the awards. Its regular theatrical release followed in August of the same year.

In the spring of 2023, Fehlbaum directed the English-language film "September 5" about the 1972 Munich Olympic attack. Featuring an almost entirely international cast alongside lead actress Leonie Benesch, the film premiered at the Venice International Film Festival in August 2024. Its German theatrical release took place in January 2025. At the 2025 Golden Globe Awards, "September 5" was nominated for Best Motion Picture - Drama.