The excellent Valancourt Books http://www.valancourtbooks.com are republishing (after long neglect) several of the novels of J.B. Priestley.
That Priestley's work is so variously assessed is, at one level, understandable and yet, at a deeper level, incomprehensible.
The surface distancing is intelligible because there is something in the style that is resolutely of its time and that creates a certain clunkiness. The closest analogy would be an 'old film' where the sets are obvious, the seams show and the acting is precisely that 'acting'! But allow for that, accustom yourself, and you quickly realise that you are in the hands of a master - a fine storyteller, adept manipulator of diverse genres, and consistently able to strike the depths as he carries you across the plane of the story (or stories).
Priestley's second novel was 'Benighted' (that was turned into a film 'The Old Dark House' by James Whale in 1932 and adapted for theatre only last year http://www.bbc.com/news/entertainment-arts-36922793).
The novel tells a familiar tale - two parties of travellers converge (and combine) in a strange house, cast there by inclement weather, and find themselves confronted by strangeness turning to horror. All of this is effectively done at the right pace and with the appropriately unnerving edge (though Whale's film deviates with an alternate ending that, ironically, softens the horror).
Priestley, however, adds several layers - each of the five visiting characters are finely drawn, helped by the device of playing the 'Truth' game to idle away the night hours - and significant themes enter into play. A marriage gone sour seeks to find a path back to meaning. A young architect describes the 'snag' of life as an inability to grasp and enjoy the now, the present endlessly postponed by anxieties, concerns, necessities. A veteran (of the First World War) tells of how it has stripped him of his purpose. A successful businessman confesses the edge that gave rise to his ruthless focusing on wealth accumulation and the exercise of power yet revealing his essential loneliness. The fine, subtle distinctions of class play about and are overcome in the confrontation with the abiding horror that is in the house.
Criticism could be applied to the counterpart of the travellers namely their hosts, trapped in their isolation and varied manias, they are underdeveloped by their author. Though perhaps you could argue that is one of the features of evil taking hold - that we refuse the complexities of our humanity and settle back into empty shells of our presumed masks. Evil is stereotypical and easily recognisable, goodness (or even ordinariness) more complicated!
Yet, on the whole, it is all beautifully (and excitingly) done.
The film (inspite of an excellent cast and admirable director) is less accomplished not least because at the last moment it tries to humanise the two principal 'evil' protagonists (and soften the ending); and, thus jars with the overall sense of human beings meeting an inhuman, even cosmic, evil. But it does have beautiful moments - Margaret distracting herself playing shadows with the candle to distract her loneliness encroached by a shadow of Morgan (the 'primitive' butler) and the first episode of violence; and, the beautiful playing of Miss Femm, the sister of the house and deranged religious fanatic whose God is wholly vengeful (and on her side)!