Note: Having grown up in Dortmund, North Rhine-Westphalia, West Germany, according to the untitled 2003 introduction to "Mein erster Fall und zwei weitere Horror-Klassiker" he worked as editor for Lübbe in the beginning of the 1970s, occasionally contributing to various digest series as author. With the success of the first adventures of "John Sinclair" he decided to focus on his work as author; he also still did some editorial work, for example choosing the cover art pieces for John Sinclair (as disclosed in that magazine's issue #1171 from the year 2000). As of 2022 the author lived in Refrath, Bergisch Gladbach, North Rhine-Westphalia, Germany After 1982 Helmut Rellergerd used the pseudonym Jason Dark exclusively, according to Florian Hilleberg's 2023 nonfiction book "Dunkle Legenden" on the 'John Sinclair' series.