As the successor of Manfred Krug and Charles Brauer he investigated from 2001 to 2008 as Tatort-homicide detective Jan Casstorff along with Tilo Prückner as Commissioner Holicek and Julia Schmidt as Jenny Graf for the NDR. The Tatort episode "Und tschüss" in February 2008 also meant the departure of Atzorn's investigator team.
He was also seen in 2002 Dieter Wedel's miniseries Die Affäre Semmeling as mayor Klaus Hennig. In the romantic comedy Kiss Me, Chancellor (2004) he slipped into the role of a head of government who falls in love with a maid, played by Andrea Sawatzki. Also in 2004 he was before the camera in Das Kommando [de], as the commander of a special unit, with his sons Jens and Daniel, who made his debut in the film as an actor. 2005 Atzorn took over the role of the chancellery chief in the series Kanzleramt. In the ZDF production Africa, mon amour (2007) he played opposite Iris Berben, as occurred with Matti Geschonneck's Wer liebt, hat Recht and in Das Kommando. In the TV drama Mein Mann, der Trinker he played in 2008 with Franziska Walser a couple whose marriage is put to a severe test. 2008 after a long break came with two new episodes of the adventure series Der Kapitän, in which he portrayed from 1997 to 2000 already the figure of Captain Frank Harmsen.
Robert Atzorn is married since 1976 with Angelika Hartung, both have two adult sons.