The Alchemist's Ruse

From the introduction: The adventurers come to know of a newly opened tavern, one owned by a half-orc named Dronk. Since its opening a month ago, people started disappearing in the neighborhood and some say it’s the half-orcs fault. It’s up to the adventurers to discover the truth. A 5-8 hour adventure for 4-6 8th-9th level characters playing the Out of the Abyss story (during the downtime between first leaving the Underdark and going to back Gauntlgrym) or as a side quest, independent of any story.