Supernatural activity in Sunnydale increases immensely during a time when Giles is away at a conference. Buffy and cohorts fight these beings to the best of their ability but must stop the source of the beings before they overrun the world. They travel to Boston, to the home of the Gatekeeper, who's house is a magickal mansion containing thousands of rooms, all of which prevent creature from roaming free over the Earth and wreaking unimaginable destruction.

The only problem they find is that the Gatekeeper is dying and his heir has been captured by the Sons of Entropy who are working to bring down the gatekeeper and unleash the demons on Earth.

This book has some of the best elements of the TV show and is strongly plotted and well written, but then these are the two best Buffy writers in my opinion. A worthwhile read during the gap between series.