From the publisher:
Spice up your game with imaginative planar locations like you?ve never seen! Don?t know what?s on the other side of that portal? Did your characters suddenly plane shift to another dimension? No problem. Just open this book, and away you go.
It's a Planescape Reunion!
Beyond the scope of the mundane world lie the infinite planes: realms of gods and demons?and treasures beyond imagining. Four veteran game designers from the classic Planescape setting have reunited to write this collection of 18 modular new planar locales.
Each plane is fully described and ready for exploration; together they form a complete cosmological framework for any campaign. The book also contains dozens of new monsters, NPCs, magic items, and spells unique to these planes.