I wrote about those two books and Shawn's whole career as a writer for the most recent print issue of Rain Taxi. While you'll have to get your hands on the dead tree magazine itself to read it all (for now), here are three paragraphs from it to whet your appetite...
More than a decade after The Designated Mourner, Grasses of a Thousand Colors received its world premiere in London (a city that has been more hospitable to [Shawn's] plays than any other). Soon after, Essays was published, collecting, in fewer than 200 pages, more than twenty years of occasional writings, including interviews with the linguist and activist Noam Chomsky and the poet Mark Strand. Shawn breaks his essays into two groups: "Reality" (mostly political commentary) and "Dream-World" (commentary on the arts), and these twin realms could apply as easily to Grasses of a Thousand Colors, wherein a wealthy and successful scientist begins by reading from his memoir (in which he justifies the work that, we soon realize, destroyed the Earth's food chain), continues by talking about his high regard for his penis, moves into a surreal and erotic variation on elements from the old story of "The White Cat" by Madame d'Aulnoy, and ends with the borders between the dream-world and reality unclear. The scientist, named alternately in the Theatre Communications Group edition of the script as The Memoirist, Ben, and He, is as unreliable a narrator of his life as any of Shawn's other characters, though perhaps more obviously compromised in his morality -- he did, after all, intentionally develop a way for animals to benefit from cannibalism. That an apocalypse of the world's digestive tracts was an unintended result is little consolation.
Food has long been a motif in Shawn's work, and the ability to gain nutrition from food or not is at least a momentary subject in almost all of his plays. Vomiting is, in fact, a common topic of conversation among his characters, as if their bodies recognize the repugnance of their thoughts and actions more than their conscious minds do. Food is related not only to sustenance, but to desire, much like sex, and Grasses of a Thousand Colors links the two appetites vividly.
What Grasses of a Thousand Colors seeks to do to its audience is less clear than in any of Shawn's plays since A Thought in Three Parts. In their relentless critique of the justifications we employ to maintain an image of ourselves as good and moral people, Aunt Dan and Lemon, The Fever, and The Designated Mourner felt in some ways like dramatizations of utilitarian philosopher Peter Singer's essays, but Grasses poses fewer clear questions and instead returns the audience to an environment in which we wonder both "Am I like these people?" and "What are these people like?"