Pop quiz question: Can you name a single writer darker than Dostoevsky? The options are few, but I hereby nominate Adam Rapp, the playwright and novelist whose vision is so unrelievedly grim he makes that despairing giant of Russian literature seem like, oh, maybe P.G. Wodehouse. Rapp's singularly gloomy weltanschauung is on stark display in […] The post Review: A return to gloom in 'The Sound Inside' appeared firs…