Introverted scholar Percival Endicott Whyborne wants nothing more than to live quietly with his lover, ex-Pinkerton detective Griffin Flaherty. Unfortunately, Whyborne's railroad tycoon father has other ideas, namely hiring Griffin to investigate mysterious events at a coal mine. Whyborne, Griffin, and their friend Christine travel to Threshold Mountain, a place of dark legend even before the mine burrowed into its heart.

Repressed scholar Percival Endicott Whyborne has two skills: reading dead languages and hiding in his office at the Ladysmith Museum. After the tragic death of the friend he secretly loved, he's ruthlessly suppressed any desire for another man. So when handsome ex-Pinkerton Griffin Flaherty approaches him to translate a mysterious book, Whyborne wants to finish the job and get rid of the detective as quickly as possible. Griffin left the Pinkertons following the death of his partner, hoping to start a new life. But the powerful cult that murdered Glenn has taken root in Widdershins, and only the spells in the book can stop them.

Whyborne’s Endicott relatives have returned to collect on the promise he made to help them take back their ancestral manor from an evil cult. In exchange, they’ll give him the key to deciphering the Wisborg Codex, which Whyborne needs to learn how to stop the masters. To that end, Whyborne, his husband Griffin, and their friends Iskander and Christine travel to a small island off the coast of Cornwall. But when they arrive at Balefire Manor, Whyborne must not only face the evil within the ancient mansion, but the painful truth about his own destiny.

On the return voyage from Balefire Manor, Whyborne receives the worst news possible: Widdershins has fallen before the onslaught of the Fideles and their servants. There’s still time to stop the return of the Masters, but that window grows shorter by the hour. Together with Christine and Iskander, Whyborne and Griffin must reach Widdershins to face the ultimate test and decide the fate of the world, once and for all.

Whyborne's lover, dashing ex-Pinkerton detective Griffin Flaherty, agrees to prove Allan's innocence. But when Allan is deemed insane and locked away in the Stormhaven Lunatic Asylum, Griffin finds himself reliving the horrifying memories of his own ordeal inside a madhouse.

Between his bullying father and dissolute brother, Percival Endicott Whyborne has quite enough problematic family members to deal with. So when his sister returns to Widdershins asking for help solving the mystery of a derelict ship, Whyborne is reluctant to get involved. Until, that is, a brutal murderer strikes, leaving Whyborne and his lover Griffin no choice but to take the case. The investigation leads them deep into a conspiracy of blackmail, murder, and darkest sorcery.

Sorcerer Percival Endicott Whyborne and his husband, Griffin Flaherty, have enjoyed an unprecedented stretch of peace and quiet. Unfortunately, the calm is shattered by the arrival of a package from Griffin's brother, Jack, who has uncovered a strange artifact while digging for gold in Alaska. The discovery of a previously unknown civilization could revive the career of their friend, Dr. Christine Putnam, or it might kill them all if the hints of dark sorcery surrounding the find are true.

Between his father's sudden - and rather suspicious - generosity, and his own rash promise to help Christine plan her wedding, Percival Endicott Whyborne has quite enough to worry about. But when the donation of a mysterious codex to the Ladysmith Museum draws the attention of a murderous cult, Whyborne finds himself in a race against time to unlock its secrets first. Griffin has a case of his own: the disappearance of an historic map, which quickly escalates to murder.

When Griffin's past collides with his present, will it cost the lives of everyone he loves? Between the threat of a world-ending invasion from the Outside and unwelcome revelations about his own nature, Percival Endicott Whyborne is under a great deal of strain. His husband, Griffin Flaherty, wants to help - but how can he, when Whyborne won't tell him what's wrong?

Librarian Sebastian Rath is the only one who believes his friend Kelly O’Neil disappeared due to foul play. But without any clues or outside assistance, there’s nothing he can do to prove it. When bookbinder Vesper Rune is hired to fill the vacancy left by O’Neil, he receives an ominous letter warning him to leave. After he saves Sebastian from a pair of threatening men, the two decide to join forces and get to the truth about what happened to O’Neil.