Xena: Warrior Princess S02 E07 Intimate Stranger

"Her courage will change the world!"

Callisto makes a bargain with Ares, from Tarturus, to switch bodies with Xena, sending Xena into Tarturus and freeing Callisto. Xena, in Callisto's form, makes her own bargain with Hades, to make things right but the only problem is...she has one day to fix it.