Reid mentions Richard Trenton Chase, a paranoid schizophrenic who was convicted of murder in 1978. He started out killing and eviscerating animals and eating their entrails, and moved up to humans. The bloody rings made by the unsub's containers in this episode were found at Chase's crime scenes. He suffered from many delusions including the "alien" one mentioned by Reid.
Gideon mentions seeing the White Sox win the world series on his list of things to do before he dies, coincidentally that same year the White Sox would win their first world series title since 1919.
Doug Jones who portrays Domino Thacker in this episode, returns in the season 4 episode Brothers in Arms as a completely different character (the fight club captain).
3 actors in this episode have been on Buffy the Vampire Slayer (1997). Lindsay Crouse who plays Mary Mays in this episode is Maggie Walsh throughout Season 4. Doug Jones who plays Domino Thacker was one of the Gentlemen in Hush (1999). Brian Turk who plays Jess Maynor plays Mort (a member of Harmonies gang) in Real Me (2000)
A Gulfstream G550 costs around $3,600 an hour to operate.