You play as Alastair, a 19th century researcher who has devoted his life to the study of the Four Horsemen. Upon hearing reports of their arrival to Earth, Alistair realises that he may have the solution to save mankind from annihilation...
This review may contain spoilers
Definitely belongs to the top custom stories. Focused on detail, atmosphere, storyline and originality, The Four Horsemen offers an excellent custom story experience which can easily amaze the player. A few the puzzles are rather hard and there's not much oil if you're not searching thoroughly. I believe I had been tracking this CS once before it was released and I think it'd been in development for a pretty long time. Now I understand why. All the effort that was put into this fine piece of hard work has proved to be reasonable.
I only found one bug - when you're going back from the Death's Quarters and load an autosave, the passageway that is supposed to be unblocked might still be blocked. This bug can be avoided by loading an earlier save or autosave. (I loaded an autosave before I went to the room with the orb and it worked.)