Cavern of the Violator

Publisher's blurb: When local farmer Jonas Cappa goes missing while hunting mushrooms and then reappears, hours later, naked and without any of his belongings, his wife goes to the party to investigate. Jonas claims to have fallen into a whole in the ground, but none can be found. What really happened to him and can it be stopped before things get worse? A one-shot adventure for characters of levels 1-4 designed to be dropped into any campaign.