Sherlock Holmes: Cthulhu Mythos Adventures. Sherlock Holmes Adventures in Time & Space, #2

Beyond London's Baker Street is a world of shadows, a world of ancient secrets and elder beings that were old before Man first appeared. At times, those eldritch entities reach from the past into the present, looming over us like a shadow out of time. Few can counter the horror of their presence with cold logic, with nerves that will not snap, with the adaptive cunning needed to survive when reality seems subsumed by madness.
Sherlock Holmes is such a man. In these stories, related from various points of view, Holmes stands between humanity and the dark forces seeking to dominate the world. Included in this collection is "The Adventure of the Ancient Gods, " the first-ever story blending the world of Sherlock Holmes with the Cthulhu Mythos stories of fantasy writer HP Lovecraft.