Insidious is an Advanced Dungeons & Dragons adventure for 3-6 characters of levels 1-3. The first print run had a size of 250 copies.
The adventure shows the AD&D 1st Edition logo, but is not an officially licensed AD&D product.
From the back of the book
The once peaceful town of Sheridan Springs is in dire trouble. Several townsfolk are missing. Strange creatures have been seen moving in the woods around town. At night, sounds that chill the soul can be heard coming from the town cemetery and the ruins north of town. Some even say that the dead are restless and walk again.
The town sheriff has sent an urgent request for aid. Will your young and inexperienced group of adventurers heed the call? Fame and reward await those that can identify and defeat the evil menacing the town of Sheridan Springs.
TSR1 - Insidious is a stand-alone adventure. It was written using rules for Advanced Dungeons & Dragons, but by changing a few statistics it can be used with any fantasy role-playing system.
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