Willow casts her "Will Be Done" spell during "Something Blue", but it has some dire consequences. The spell isn't reversed, and Willow goes somewhere she can't return from.

The aftermath of Willow's spell causes heartache for all the Scoobies.

A full blown Scoobie study session leads to a heap of information they could have all lived without.

Buffy makes a decision...of the eternal kind. Xander takes matters into his own hands.