In the Middle Ages, and even up to the early twentieth century, most of Europe's executioners were related: the Sansons and Deiblers in France, the Pierrepoints in England, etc. The reason for this was that, it generally not being socially acceptable to, well, kill people, executioners and their children could, generally, only marry other executioners or their children.
The parallels with massively inbred, Hapsburg-style dynasties are obvious- imagine a rather clever but politically inept satirist noting this, and being sentenced by the latter to a meeting with the former; even worse, imagine a dynasty of deranged and deformed executioners- think Texas Chaisaw Massacre with government funding.
With regard to the plot "Sleeping Mines of Elathon":
You manage to get the water wheel in the mine working which operates a pump to clear the flooded lower levels. As you explore the dank tunnels of the lower galleries, you can hear the creaking of the wheel above. You enter a low-ceilinged passage and are crawling on your backs, when the creaking stops. The water starts seeping wetly around the back of your head...