From the back of the book:
In the Caves Everyone Can Hear You Scream!
Something sinister is happening in the village of Scarborough, and you've been hired to find out what. But what you'll find is even worse than you can imagine.
Are you up to the challenge?
"The Horror Beneath" is a d20 System fantasy adventure for levels 3-5. It is a complete adventure for 4-6 players. It includes everything needed to play. It is set in the World of Vallkan, and includes a preview of "Black Powder Gods", the next book set in this world.