A reclusive writer is visited by the ghost of Edgar Allan Poe, asking for help in elucidating the mystery surrounding his death. Using a magical pocket watch, the writer is able to travel to the past to investigate and find clues about Poe's demise.
Midnight Mysteries: The Edgar Allan Poe Conspiracy is a hidden object game with elements from the adventure genre, where most of the time the objective is to search and find all the items listed at the bottom of the screen, on locations filled with scattered objects. Most places and story elements of the game make allusions to the writings of the classic author, using his work as the unifying theme. Some of the list entries are clues instead of the object name, like "unlucky number" for "13" and similar riddles. A few of the collected objects are stored in the brown bag besides the list to be used later when solving puzzles. Besides the list items, there are ravens all over the scenery that can be collected for extra hints. The hint button itself is a raven perched over a lamp, that when clicked takes off flying towards one of the required objects. The lamp shows the silhouette of the list entries.
Some of the list items are written in blue, to indicate the need of an extra step or the use of an inventory object to retrieve them. The tools can be used as in most graphic adventure games, by dragging and dropping them from the inventory to an appropriate spot on the screen. In some locations, the cursor changes to two blue gears when hovering over one of the interactive portions of the scenery, sometimes bringing up puzzles that take place on a separate screen. Most of these puzzles can be solved by direct manipulation of some mechanism or key, sometimes requiring the input of a code or another clue that can be found nearby.