A cave-in at the dwarven mine exposed a passage into the eerie, alien world that lies deep below the surface. Monsters poured out of the darkness and killed many before the surviving miners made it back into the light. Now they seek brave adventurers to face the dangers down in the dark depths. As a one shot or the first adventure of a new campaign, The Eyeless in the Dark carries new and experienced players away from the light of the ordinary surface world and down into the fantastical dark depths where here there be monsters. Chock full of adventure, as well as design notes for Dungeon Masters that will help novice and veteran DMs provide their players with an exciting and memorable game night, and leave them eager for the next session. Use this adventure in combination with the Integrated Hill Encounters and/or the Forest and Grasslands to create an open world sandbox of adventures that can fill many sessions of a campaign.