No Place Like Home

In which Giles opens the Magic Shop, Joyce takes a turn for the worse, Riley feels unappreciated, a monk gets first-hand experience of Glory, and Buffy discovers that drugs can make her see the way things really are. Which is maybe not the message we were supposed to get from that.

Official back-of-box synopsis:

Buffy learns more about her 'little sister' Dawn after she discovers a mysterious orb linked to a group of monks. Buffy is even more troubled when her mother suddenly becomes ill without explanation.

From the old WB Buffy website:

ALL IN THE FAMILY - An unseen evil comes to Sunnydale that that helps Buffy discover more about her little sister Dawn and the girls are distressed and confused when their mom suddenly becomes ill without any clear explanation, medical or supernatural.

Cross-reference:

episodes in which people wear amusing clothing:

• Reptile Boy
  Xander in drag
• Fear, Itself
  Mexican Giles, Bunny Anya...
• All The Way
  Pirate Xander, Charlie's-Angel Anya
• Hells Bells
  Those bridesmaid dresses...
• this episode
  Giles is in a Wizard costume. Buffy is speechless.

Cast:

• Sarah Michelle Gellar as Buffy
• Alyson Hannigan as Willow
• Nicholas Brendon as Xander
  

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• Anthony Stewart Head as Giles
• Kristine Sutherland as Joyce
• James Marsters as Spike
• Emma Caulfield as Anya
• Marc Blucas as Riley
• Amber Benson as Tara
• Michelle Trachtenberg as Dawn
• Charlie Weber as Ben
• Clare Kramer as Glory
• Paul Hayes as Older Night Watchman
• Ravil Isamov as Monk
• James Wellington as Night Watchman
• Staci Lawrence as Customer
• John Sarkisian as Old Monk