A "mushi" aren't quite physical, aren't quite spiritual, but the molecular, abstract forms have always existed. They're mostly innocuous, though occasionally pernicious, like when certain species nestle themselves into the eyes or ear canals because they "eat" light and sound. Only certain kinds of people can even perceive the mushi, and that's where a wandering one-eyed man named Ginko, a mushi master (mushi-shi), steps in.
An anthology following Ginko's exploits solving mushi-related afflictions in the far-reaching towns during Edo-era Japan, Mushishi is supernatural and soft around the edges. It leaves you feeling generally positive about the motives of humanity, even when stories aren't neatly resolved. Don't expect sword fights or high-intensity action here, folks. This is meditative, tactfully told anime. The dumb news is that only Season 2 is on Netflix -- you'll have to scoot over to Hulu for the first 26 episodes of the series. But, as mentioned, you can start watching from pretty much wherever and still get the point. It's best to ride this one slowly.