Creatures of the Pool by Ramsey Campbell (2009)

Creatures of the Pool by Ramsey Campbell (2009): Gavin Meadows, self-employed as a walking-tour guide of historic Liverpool, finds out more about the city's long (founded in the 13th century) and somewhat bizarre (even in non-fiction) history as he searches for his missing father. 

Ramsey Campbell grew up in Liverpool, and a number of his previous novels have been set either there or in his early-career Liverpool stand-in, Brichester. Here, he visits all-out historical horror on his home, blending real and fictional in an unnerving, escalating fashion that builds upon the quasi-documentary accumulation of detail so central to H.P. Lovecraft's best work.

Campbell uses first-person narration here as he did in his previous novel, The Grin of the Dark. As first-person narration had previously been rare in Campbell's long-form output, I wonder if he had more ideas related to unreliable narration than The Grin of the Dark could profitably address. Gavin Meadows is much more reliable than the narrator of the previous novel, but we do get some (self-doubting) moments as Meadows tries to wrestle with whether or not what he's glimpsing is real or somehow an ongoing hallucination brought on by stress.

See, Liverpool was built partially on reclaimed marshland and, indeed, a reclaimed pool. Beneath the ground, ancient tunnels proliferate, some now being rediscovered, some still hidden. Above the ground, the rain seems to fall incessantly. And everywhere and increasingly, Gavin starts to see things that don't appear to be quite human, even as the police seem to take his father's disappearance lightly. And as Liverpool gradually succumbs to a rising damp, Meadows struggles to keep his own thoughts straight against the onslaught of historical facts that sometimes threaten to overwhelm his reason.

Long-time horror readers will recognize Campbell's nods to Lovecraft's "The Shadow over Innsmouth" and "The Festival", though this is in its own odd way a much 'gentler' story, or at least a more ambiguous one related to the malignity of Liverpool's 'other' residents. Still, if you're ever in Liverpool, you may want to avoid drinking the water. Or bathing in it. Highly recommended.