Wikipedia a dit :

A lengthy, complex novel featuring a large cast of characters, the narrative is set primarily in Europe at the end of World War II and centers on the design, production and dispatch of V-2 rockets by the German military, and, in particular, the quest undertaken by several characters to uncover the secret of a mysterious device named the "Schwarzgerät" ("black device") that is to be installed in a rocket with the serial number "00000".