For more than two decades, August Diehl has been one of the leading figures of the German film and theatre scene. He first gained widespread recognition with his role in Hans-Christian Schmid's 23. In a series of films, including Kalt ist der Abendhauch, Tattoo, Love in Thoughts (Was nützt die Liebe in Gedanken), Distant Lights (Lichter), The Ninth Day (Der neunte Tag), the Academy Award-winning The Counterfeiters (Die Fälscher), Freischwimmer (Head Under Water), Dr. Alemán, and Buddenbrooks, he demonstrated his remarkable versatility as an actor.
In 2009, he appeared in Quentin Tarantino's Inglourious Basterds, followed in 2010 by Salt, directed by Phillip Noyce.
On stage, Diehl has delivered acclaimed performances at theatres in Berlin, Hamburg, Zurich, and Vienna, appearing in productions such as The Seagull, Don Carlos, The Jew of Malta, and Major Barbara. He has worked with directors including Luc Bondy, Klaus Michael Grüber, and Peter Zadek, with whom he collaborated on three productions. His television work also includes Kabale und Liebe, directed by Leander Haußmann.
For Lars Kraume's The Coming Days (Die kommenden Tage), Diehl appeared alongside Daniel Brühl, Johanna Wokalek, and Susanne Lothar. The film was released in German cinemas in 2010. In 2011, he portrayed Bernward Vesper in Andreas Veiel's If Not Us, Who? (Wer wenn nicht wir), for which he received a nomination for the German Film Award. The film tells the story of the generation that preceded the emergence of the Red Army Faction (RAF) and was selected for the official competition of the 2011 Berlin International Film Festival.
In 2011, Diehl filmed Confession (Confession of a Child of the Century) alongside Charlotte Gainsbourg and Pete Doherty. The film premiered in the Un Certain Regard section of the Cannes Film Festival in 2012. During the winter and spring of 2012, he filmed Layla Fourie in South Africa under the direction of Pia Marais; the film had its world premiere at the 2013 Berlin International Film Festival. Also in 2012, he appeared in Bille August's international co-production Night Train to Lisbon, which likewise premiered at the 2013 Berlinale. His further film credits include The Young Karl Marx (Raoul Peck, 2015), Allied (Robert Zemeckis, 2016), A Hidden Life (Terrence Malick, 2019), Plan A (Doron and Yoav Paz, 2021), and Der Räuber Hotzenplotz (The Robber Hotzenplotz, Michael Krummenacher, 2022).
In recent years, Diehl has worked extensively on international productions, including Sidonie in Japan (Élise Girard, 2023), The Disappearance of Josef Mengele (Kirill Serebrennikov, 2025), The Ice Tower (La Tour de Glace, Lucile Hadžihalilović, 2025), and The Rays and Shadows (Les rayons et les ombres, Xavier Giannoli, 2025). At the 2026 Cannes Film Festival, Fatherland, directed by Paweł Pawlikowski, had its acclaimed world premiere. This film, together with Beautiful Souls (Schöne Seelen) by Tom Schreiber, was also presented at the 2026 Munich Film Festival.
Diehl has also played leading and major roles in notable television and streaming productions, including Perfume (Philipp Kadelbach, Netflix/ZDF, 2018), The New Era (Die neue Zeit, Lars Kraume, ZDF, 2019), and Pagan Peak (Der Pass, Christopher Schier, Sky, 2022). In spring and summer 2026, he is filming Boys from Brazil for Netflix.
In 2012, Diehl returned to the major theatre stage with The Prince of Homburg, directed by Andrea Breth in Vienna and Salzburg. His artistic collaboration with Andrea Breth continued with Hamlet at Vienna's Burgtheater, for which he received the Nestroy Theatre Award in 2014. The acclaimed six-hour production was widely celebrated. He also appeared at the Burgtheater in The House of the Spirits (Das Geisterhaus), and at the Akademietheater in John Hopkins' The Story of Them (Die Geschichte von Ihnen). Diehl reunited with Andrea Breth for Long Day's Journey into Night at the Burgtheater in 2018 and Three Lives (Drei Mal Leben) at the Berliner Ensemble in 2019. His artistic collaboration with Kirill Serebrennikov has also continued on stage, most recently in The Blizzard (Der Schneesturm) at the Düsseldorfer Schauspielhaus (2025/2026).
For his outstanding performance in The Disappearance of Josef Mengele, Diehl received the German Film Award for Best Actor in 2026. It was the second German Film Award of his career since 23.