A monastery on an island in a swamp.
An ancient evil kept at bay by the corpse of a saint.
An Elf-Maid enchanting men to their doom.
Demons of fire waiting centuries for revenge.
You get all this and more in RPGPundit Presents #76: Fire Demons of Croyland (https://www.drivethrurpg.com/product/274535/RPGPundit-Presents-76-Fire-Demons-of-Croyland)! This is a Medieval-Authentic adventure scenario, playable with Lion & Dragon (https://www.drivethrurpg.com/product/226022/Lion--Dragon)or any other OSR RPG (though you could also play it with any edition of D&D or other fantasy games).
(https://2.bp.blogspot.com/-3r8wPH-1ufU/XMqlwObTPSI/AAAAAAAAEK8/UQ0qZL9-ZDcqb5wxlVseH3IFNk7GP_7AwCLcBGAs/s320/76img.jpg)
Fire Demons of Croyland has the PCs in a tiny community in an isolated area, where things are about to seriously hit the fan, due to the combination of an ancient evil and an Elf-maiden seeking to unleash it. It combines classic adventuring with elements of investigation, and plenty of role-playing opportunities.
It's just $2.49, so be sure to purchase RPGPundit Presents #76: Fire Demons of Croyland at DTRPG (https://www.drivethrurpg.com/product/274535/RPGPundit-Presents-76-Fire-Demons-of-Croyland), or from the Precis Intermedia Webstore. (http://www.pigames.net/store/product_info.php?products_id=1012)