Between the saucy carnival of the Georgians and the splintered genius of the moderns, the Victorians seem like a marble slab of respectability. Very fine and very deathly. The Essex Serpent is not about those marble Victorians. Sarah Perry’s second novel – a follow-up to her eerie 2014 debut, After Me Comes the Flood – contains many things that are unlikely, edging toward supernatural. There is early open heart surgery, hypnotism, contagious hysteria, and of course, the serpent of the title (which may or may not be ravaging the Essex shoreline). But the characters who inhabit Perry’s historical fiction are fundamentally like the Victorians of life rather than the ones of myth: a mix of the curious, the crankish, the sceptical and the devout, the upstanding and the down-low.