I'd like to live just long enough to be there when they cut off your head and stick it on a pike as a warning to the next ten generations that some favors come with too high a price. I would look up at your lifeless eyes and wave like this. Can you and your associates arrange that for me, Mr. Morden?
The history of the war between the Shadows and the other races, including the First Ones, is described for the first time.
This episode was originally intended to air after "Knives", rather than before, with Sheridan's hallucination of the Icarus in that episode serving as a reminder to the audience of his wife's fate before more details were revealed in this episode.
The name Z'ha'dum can be seen as a homage to Tolkien's Khazad-dûm (Moria) in Middle Earth. Just as Khazad-dûm has been abandoned for many years, and is now inhabited by an ancient evil, so too Z'ha'dum, once the home of a mighty civilization, is now the home of an ancient and deadly evil.