"The Alchemist" is a short story by H. P. Lovecraft, written in 1908, when Lovecraft was 17 or 18, and first published in the November 1916 issue of the United Amateur.
Plot summary:
The story is recounted by the protagonist, Count Antoine de C-, in the first person. Hundreds of years ago, Antoine's noble ancestor was responsible for the death of a dark wizard, Michel Mauvais. The wizard's son, Charles le Sorcier, swore revenge on not only him but all his descendants, cursing them to die on reaching the age of 32...