Inca Mummy Girl

In which Buffy and Cordy host exchange students, Willow dresses as an Eskimo, Giles suffers a head wound, and Xander woos a girl with Twinkies. (Exhibit C in the 'Xander is Hot' debate)

Official back-of-box synopsis:

A Peruvian exchange student stirs up Buffy's and Giles's suspicions when a student goes missing on a field trip to the Natural History Museum, but Xander is the one who's really in jeopardy when he falls for the ravenous beauty.

From the old WB Buffy website:

MUMMY MAY I -- Buffy and Giles are suspicious of Ampata, a Peruvian exchange student staying at Buffy's house, when a fellow student goes missing during a school field trip to the Natural History Musueum and a broken Peruvian pictogram-cover plate is found in his place. Meanwhile, after Xander falls head over heels for Ampata, he faces certain death when his love interest is revealed to be an ancient mummy who must kill to stay alive.

Links:

This episode's page at http://www.restlessbtvs.com/, the Restless BTVS Trivia Guide

This episode's page at http://www.vrya.net/bdb/, the Buffyverse Dialog Database

Cross-reference:

episodes Featuring Major Moments In Xander's Love Life:

• Teacher's Pet
  The teacher he's hot for is a preying matis
• The Zeppo
  he loses his virginity: everyone's looking the other way
• The Harsh Light Of Day
  Anya, basement, cran-apple juice everywhere
• this episode
  Ampata nearly sucks the life out of him

episodes in which people wear amusing clothing:

• Reptile Boy
  Xander in drag
• Halloween
  Some of the clothing is deadly serious, but Caspar!Willow and Pussycat!Cordy are unforgettable
• Fear, Itself
  Mexican Giles, Bunny Anya...
• Doomed
  Spike in Hawaiian shirt and boardshorts. Somehow he's still sexy.
• No Place Like Home
  Giles is in a Wizard costume. Buffy is speechless.
• All The Way
  Pirate Xander, Charlie's-Angel Anya
• Hells Bells
  Those bridesmaid dresses...
• this episode
  The Cultural Exchange costume dance

episodes in which Sunnydale acquires new transport mechanisms:

• What's My Line? (part 1)
  Kendra arrives at the airport
• Surprise
  Angel intends to leave from the docks
• Crush
  Dru arrives by train
• this episode
  Sunnydale bus depot. Classy! What better way to introduce Ampada to our country?

Cast:

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

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• Anthony Stewart Head as Giles
• Charisma Carpenter as Cordelia
• Kristine Sutherland as Joyce
• Seth Green as Oz
• Jason Hall as Devon
• Danny Strong as Jonathan
• Ara Celi as Ampata
• Henrik Rosvall as Sven
• Joey Crawford as Rodney
• Kristen Winnicki as Gwen
• Gil Birmingham as Peru Man
• Samuel Jacobs as Peruvian Boy