From publisher blurb:
Beneath Thunderspire Mountain lies a sprawling network of mazes, tombs, and caverns collectively known as the Labyrinth of Lost Souls. In recent years, this vast labyrinth has become a living dungeon from which trade between the surface and subterranean worlds is possible. However, beyond the well-lit halls where prospectors, merchants, and traders convene lies a darker world where adventurers battle monsters and fiendish beings perform secret rituals for their dark masters.
H2 Thunderspire Labyrinth is a D&D adventure designed for heroic-tier characters of levels 4th-6th. It is the second adventure in a three-part series that began with H1 Keep on the Shadowfell and concludes with H3 Pyramid of Shadows. It can also be played as a stand-alone adventure.
This product includes an adventure booklet for the Dungeon Master, a player's booklet containing new character options and campaign information, and a full-color poster map.