This is a play about sex. Bawdy, funny, provocative and downright weird, it’s the first new work in more than a decade from Wallace Shawn, an underappreciated master among contemporary dramatists, who is still probably best known for his appearances in The Princess Bride and — as the man who sexually “opens up” Diane Keaton’s character Mary Wilkie — in Woody Allen’s Manhattan.

Here, headily, Shawn is in full “opening up” mode. Set in the near future, yet utterly immediate, Grasses Of A Thousand Colours anatomises the erotic. It’s a hymn to the penis that also proves a delicious celebration of female carnality.

Initially this isn’t clear. The main character, a scientist called Ben who is played by Shawn himself, begins by telling us he is going to read some sections of his memoirs, and there follows an extended reflection on the subject of Luck.
But soon enough, the first consonant changes. Although we are treated to several strongly phrased asides (on the politics of diet, for instance) Ben’s main accomplishment is a massive organ solo.

We witness at close quarters Ben’s relationships with three different lovers. His varied experiences enable him to characterise sex as oblivion, self-invention or obstruction — as animal act, solitary pleasure, voyeuristic rhapsody or Gothic monstrosity, and above all as a chronicle of the choices we make. Male sexuality is cherished, yet also slowly revealed to be the most insidious kind of trap.

Women’s sexuality, on the other hand, is presented throughout as something complex and puzzling. For a long time in this long play (which runs to three-and-a-quarter hours, with two intervals), the pivotal character seems to be a cat we can’t actually clap eyes on. One might think this a rather limp sub-Freudian innuendo — yet, as with so much in Shawn’s oeuvre, there’s a much better joke just waiting to be sprung.

As Ben, Shawn gives a multi-faceted performance. Often he looks puzzled, and at times he wears the vatic countenance of Yoda, but he’s also disarming, conspiratorial, fierce and wise.

Alongside him Jennifer Tilly, as his voluptuous lover Robin, is a revelation — husky, vampish, instantly memorable — while in the smaller role of the poetic Cerise, Miranda Richardson is feline and charismatic. Individually, the two women thrill, and when they intertwine in a sapphic caress the effect is bewitching.

The direction, by Shawn’s longtime collaborator Andre Gregory, is dextrous, and Eugene Lee’s set is intimate and elegantly conceived. Less convincing, yet still unsettling, are the snippets of film projected onto the set, which insinuate notes of surrealism, nostalgia and the tyrannical unconscious. 

Inevitably, elements of the play will affront some theatregoers. There are repeated allusions to bestiality and masturbation, as well as less sustained ones to donkey’s genitals and incest. But Shawn’s writing possesses a remarkable mixture of unabashed intellectualism and visceral appeal, and Grasses Of A Thousand Colours is richly textured, original and wickedly amusing.