After Sean Astin told writer/director and close friend Douglas Petrie about his "fervent desire to be directing episodic television," he shadowed producers David Greenwalt and Tim Minear for several weeks to get a feel for the series before he was given this episode to direct. "Television sort of mandates that you keep moving," Astin says, "but you don't want to stop. Angelus [has] so many layers and so many different shades and qualities, you want to keep exploring them and mining them and pulling them out. It's such a rich, meaty character for him to do. He's good at evil. It's a little creepy."
When Connor is confronting Angelus, Angelus mocks him by saying "Doin' your mom and trying to kill your dad--there should be a play." This is a sarcastic allusion to Oedipus Rex, the ancient Greek play wherein the hero is, by prophecy, condemned to kill his father and sleep with his mother. The plot of this play also inspired Sigmund Freud's concept of the "Oedipus complex" in his semi-extreme psychoanalytic theories.
Angelus refers to Fred and Gunn as Othello and Desdemona, and the line "Bodies, bodies everywhere, and not a drop to drink," is a reference to a similar line in The Rime of the Ancient Mariner.
Angelus's reference to the "foul rag-and-bone shop of the heart" comes from the William Butler Yeats poem "The Circus Animals' Desertion", and that animalistic element is also present in his choice of music in his cage at the beginning, "The Teddy Bears' Picnic", a song which, later in the lyric, promises good things to the good, but also speaks of watching them (the bears) and "catch them unawares".