April 14, 1865: Edgar Allan Poe and Olimpia have pursued Dr. Coppelius into the future. But it is a future unlike any they could have imagined.

The mad doctor's trail has led them to Washington D.C. On their first night in town, innocently taking in a play at Ford's Theatre, the pair witness a scene that will forever change the course of history: the assassination of a president.

But not just any president—a clockwork president. Coppelius's handiwork has been uncovered, a Clockwork Conspiracy to bring down the government exposed, and the assassin, John Wilkes Booth, has become the hero of the day.

It is a tumultuous time for the country. Slavery has been abolished, but rancor seethes in the old south. Multiple attempts have been made on the president's life and a mysterious disease—known as The Red Death—is sweeping the city. Called upon by Abraham Lincoln himself, Edgar Allan Poe will assist a grudging Detective Allan Pinkerton in protecting the president. Together, they must uncover the source of the unrest and its links, if any, to the dreaded Red Death and the fugitive Dr. Coppelius.

The team quickly learns that Booth is, perhaps, not all the hero that he seems. Poe and Olimpia soon find themselves embroiled in a conspiracy that leads them to the infamous mesmerist, Professor Nicolai Constantine, whose powers have captivated the city, including the occupants of the White House itself—and to a certain strange clock tower whose clangorous bells toll only at midnight.

A Midnight Dreary is the second book in the Poe Files Mysteries begun in My Clockwork Muse.