Giles and Anya’s Halloween costumes (a mexican and a bunny) from Fear, Itself were so popular with fans that they were made into action figures by Clayburn Moore.

In Fear, Itself, Xander calls Buffy “Red”. Spike called Willow “Red” in Same Time, Same Place and The Yoko Factor, and Faith called Willow this in This Year’s Girl. Kennedy also calls Willow “Red” in Chosen, when they’re in the Principal’s office getting ready for Willow to work her mojo.

Scooby Halloween costumes Fear, Itself include: Buffy as Little Red Riding Hood; Willow as Joan of Arc; Oz as God; Xander as James Bond (or a waiter); Anya as a bunny; and Giles as a Mexican.

Tucker Gates directed the episode Fear, Itself. He directed the Angel episode ‘Hero’. Tucker has also directed episodes of Skin, CSI: Miami, Roswell, Providence, Cracker, Dark Skies, and The X Files.

The following is from the original script for Fear, Itself:
Willow: “Oz!”
Xander: “Will!”
She appears, moving down the hall.
Xander: “We’ve got trouble. There’s something terribly wrong with Buffy. She can’t even tell that I’m –”
Willow: “Oz!”
Xander stops, defeated. She can’t see him, either. She looks around, upset.
Willow: “Oh, God…Okay, guiding spell. Okay. …

Sulo Williams played Chaz in Fear, Itself (the frat guy who said Arbor Day was the only holiday not about getting laid) and in Hush. He also played Puff Dog in Passions.

Walter Emmanuel Jones, who played Edward (the frat guy who painted the pentagram) in Fear, Itself, starred as the Black Power Ranger in Mighty Morphin’ Power Rangers. He also starred alongside Charisma Carpenter in Malibu Shores and has been in Love And A Bullet and American Gun.

Singer Bif Naked performs ‘Moment of Weakness’ and ‘Anything’ at the campus party in The Harsh Light of Day, where Buffy runs into Spike and Harmony. Her song ‘Lucky’ plays as Buffy and Parker dance.

The album that Oz holds up at Giles’ house in The Harsh Light of Day is ‘Loaded’, the Velvet Underground’s 1970 album.

Harmony asks in The Harsh Light of Day, “Is Antonio Banderas a vampire?” Actor Banderas played a vampire in the 1994 movie Interview With The Vampire, which also starred Tom Cruise. In the film Banderas played Armand, a 400 year-old vampire who ran a theatre, where the vampire killings were …

Buffy wakes up alone after a night of sex for the second time in The Harsh Light of Day. The first was in Innocence, when Angel was busy somewhere else turning into an evil vampire. Buffy later asks if all men she sleeps with will turn evil.

Xander says in The Harsh Light of Day that Anya’s approach is surprisingly more romantic than Faith’s, referring to The Zeppo when he had sex with the rogue slayer.

In The Harsh Light of Day, Spike hurts Buffy’s left arm and she cradles it during their fight. It’s the same arm that Sunday injured in The Freshman.

In the Harsh Light of Day, Harmony says that Spike nearly killed Willow last year, which we saw in the episode Lover’s Walk.

In The Harsh Light of Day, Xander mentions Anya “fleeing in terror” in Graduation Day (Part 1). Anya refers to the fact that they went to the Prom together.