Robert Blake, a writer visiting Providence, becomes fixated on a derelict church on Federal Hill and breaks inside, where he finds the Shining Trapezohedron — a jewel that serves as a window to darkness.
From that moment the entity in the steeple — the Haunter of the Dark, an avatar of Nyarlathotep that cannot endure light — invades his mind. A blackout night ends with Blake found dead at his desk. The character is Lovecraft's tribute to his protégé Robert Bloch.