The PDF of Historica Arcanum: The Serpentine Door. 

The Serpentine Door is the prequel to the storyline of Historica Arcanum: City of Crescent, containing a mini-adventure that takes players deeper into the mystery behind the Trojan Digsite.
 
 
The Serpentine Door
 
A 5th edition adventure module
 
Page Number: 23
 
Contents:
Introduction
Adventure Summary
Act I: A Dinner at the Farmhouse
Act II: Absent Men
Act III: The Serpent and the Megaron
Appendix