Hoard of the Dragon Queen: Aftermath - Episode XI - To Gundren

Our heroes battled many foes, pressed on through magical darkness, and suffered mental distortion and influence from some unknown source. Oh, and Murry is attached to a genie's bottle. Now, here they sit. Captives in the Underdark. Prisoners of a mysterious underground amphibious race. With their arms and feet bound, our heroes stare straight ahead, viewing the long lost Gundren atop a stone altar. Will they manage escape and rescue their dwarven ally from being sacrificed? Or, will some terrible tragedy befall them?