Even though Julien Gracq was a history teacher his entire working life, his novels are not set in identifiable historical moments, rather they are evocations of fictional places that have fallen out of time and of the people who have fallen in love with these timeless oases and refuse to leave them. Julien Gracq's major influence is German Romanticism and just like the characters of German Romanticism Gracq's characters are in love with the idea of their own destruction/dissolution. Whether his characters really desire their own destruction is debatable, but they all love imagining it/prophesying it.
Gracq writes like a student (albeit a very gifted one) whose imagination is fueled by French poetry and German Romanticism and who in his own work is attempting to conjure the same strange forces. But what makes A Dark Stranger something more than a revisiting of these taditions is the way Gracq reinvents and adapts these traditions and makes them relevant for his own time. Gracq knows his Stendhal and his Goethe and his Poe but he also knows his Baudelaire and his Proust and his Mann (those writers who diagnosed the "modern" as if it were a shared malady). So A Dark Stranger does read like a Gothic Novel but one written with a pecuilarly modern sensibility.
The characters in A Dark Stranger are all independently wealthy, so like many characters in Gothic and Romantic poetry and novels they are not defined by profession but by temperament and Gracq spends considerable portions of this novel exploring each character's temperament. But unlike Gothic and Romantic literature, Gracq does not explain temperament or identity as an intrinsic or inherited thing but as a pose. Gracq's characters have romantic temperaments but they are aware that they are enacting their tragic poses and fates by choice. They are will-less creatures who nonetheless know they do have wills of their own and could change their role and fate as easily as they could change their outward attire but somehow they continually choose not to choose. Perhaps they all suffer from a paralysis of will because what they fear more than death and destruction (which they can justify as heroic) is loss of class/group connectivity. Its the strange nature of this class/group connectivity that is the real subject of this strangely attractive novel.
Everyone staying at the Hotel des Vagues shares a social or class connection but more interesting to Gracq are the deeper psychic affinities that allow individuals of various levels of intimacy (regardless of whether they are intrigued or repelled by each other as individuals) to feel that their fates are inextricably bound up in each other. It's easy to see that everyone at the hotel suffers from an excess of free time which fosters boredom but this boredom fosters an even more severe malady which is a sense of psychic loneliness. Socially they are connected, but their psychic bonds (and their attenuated subjectivities) are much more tenuous and fleeting. What allows them to feel connected to something greater than themselves is when one from their own class enacts a summerlong drama in their midst that makes them all feel that they are caught up in something quite extraordinary, quite heroic, quite tragic, and quite literary.
This is not a perfect novel, but it's an infinitely clever one. Gracq's characters profess an admiration for chess but Gracq himself is the player to keep an eye on here and you don't realize what a master he is until the last move. Though not his best work, A Dark Stranger does contain some highly wrought passages that could stand next to Gracq's best work.