The supernatural drama web series “20 Dollar Show” is an anthology of stories that place ordinary people in extraordinary circumstances, all beginning with our narrator/host handing off a $20 bill to the latest poor schnook on the hook. It’s more reminiscent of the ancient and unjustly forgotten show “One Step Beyond” than the more obvious model, Rod Serling’s timeless “Twilight Zone,” because it’s so low-key in its execution (obviously due to budget), but it does maintain a consistently intriguing if self-consciously somber mood largely due to the brooding electronic score and the relative complexity and originality of the predicaments faced by the protagonists. Like both “One Step Beyond” and “Twilight Zone,” these are essentially morality plays wrapped in the cloak of a fantastical thriller, and anyone more drawn into the human interest angles than the spooky setups will find this all fairly satisfying.