Laura Miller at Salon.com reviewed Sarah Water's fifth book, The Little Stranger, in terms that I can only completely agree with - this is a "masterly, enthralling new novel", and a serious must-read. I'm including the link to Miller's review here. There are only a few other things that I would add.
The first is to comment on the subtlety of Waters' plotting and execution. For a writer who successfully mastered the art of explicitly wrought, Dickensian plotting in Tipping the Velvet, Affinity and Fingersmith, Waters has done something truly impressive here - she has mastered, with equal or greater facility, the tightrope walk of the implicitly driven plot. Whereas her first novels were rendered in a fully Victorian style with complicated twists and last minute revelations, The Little Stranger builds slowly, implying much, confirming nothing, all the while gently stoking a tangible feeling of dread. This is a gothic ghost story sustained at perfect pitch. I doubt even Henry James could have made The Turn of the Screw work at 300 pages, and yet Sarah Waters does, drawing the reader into the decay of Hundreds Hall and unraveling its inhabitants inch by creepy inch.
The second thing I want to mention is the narrator of The Little Stranger, Dr. Faraday, whose first name we never learn. This is interesting and something I'll have to think about. Anyway, I can't say much about him without allowing my interpretation of the book to color another reader's experience, but I will say is that rarely have I ever seen dramatic irony so skillfully and thoroughly employed. Her characterization of the kindly, stable Faraday is brilliant and sad and unnerving, thanks to the ambiguity ruling the book. Faraday alone is worth the read, but it would be short-changing Waters' skill to say that he is the only reason to read The Little Stranger.
I have been a fan of Sarah Waters ever since I read her first novel, Tipping the Velvet. It was a raw and exuberant, heart-breaking book, which she followed with the emotional gut-punch of her second book, Affinity. Waters' early novels reveal a young writer tapping into and exploring her prodigious talent. With The Little Stranger, Sarah Waters has given us a fully mature work, a master-stroke in the form of a controlled, slow burn that delivers on the full weight of her potential.