By Ann-Marie MacDonald. Directed by Ellie King. A One Night Castle Projects production. At Presentation House Theatre until April 9

Ann-Marie MacDonald's Goodnight Desdemona (Good Morning Juliet) is one of the cleverest Canadian plays ever written.

MacDonald's heroine, Constance Ledbelly, struggles to complete a PhD thesis in which she argues that Othello and Romeo and Juliet turn on such simple points of ignorance that they barely earn the right to be called tragedies. She believes Shakespeare ripped off comic sources for both stories; the wise fool, that staple of comedy, is so obviously missing from both plays that she thinks the fool has been edited out.

When a crisis in Constance's personal life tips her over the edge, she finds herself spinning through Desdemona's Cyprus and Juliet's Verona, testing her thesis and turning two of literature's most monumental tragedies into farces. Constance performs the fool's function, which is to state the obvious. She blows the whistle on Iago only to find herself the victim of his plotting. And Desdemona turns out to be every bit as bloodthirsty as her Moorish husband is. When Constance interrupts the chain of events that leads to the tragic suicides in R and J by telling Tybalt that he shouldn't duel with Romeo because they have recently become cousins by marriage, she dooms the play's young lovers to a life of domestic boredom. Soon, they both have the hots for Constance, whom they think is Constantine, a comely Greek youth, and for convoluted reasons they both cross-dress to gain his favour.

The script presents a number of stylistic challenges, and the evening gets off to a bit of a shaky start. We see some Shakespearean scenes played straight, but they're not performed well enough to be credible.

And, in the first act, the level of comic originality is inconsistent. James Rowley's Othello and Jeff Gladstone's Iago are both vague. But that's not a huge problem, because Cailin Stadnyk's Constance and Leanne Koehn's Desdemona are spot-on. Stadnyk creates a lovely clown: her Constance is as timid and squeaky as a cartoon mouse, but her emotions are always true. Stadnyk is especially good at getting laughs from understatement, which makes a nice contrast to Koehn's deliciously over-the-top Desdemona. This Amazon is so obsessed with honour that she's like a trumpet blast of hyperbolic feelings.

In Act 2, all of the actors ride the same wave of inspiration, and director Ellie King's production kicks into an even higher gear. Anna Cummer's Juliet is positively visionary. This young player doesn't get a huge amount of work, but she is one of the very best in town. Here, she makes the most of MacDonald's petulant, emotionally out-of-control adolescent character. Everything in Cummer's portrait is as fresh as it is extreme. This Juliet is desperate to get plowed by something, and she doesn't much care if it's a dick, a dildo, or a dagger. Gladstone's Romeo is an appealingly polymorphous Valley boy, and Rowley makes a hilarious appearance as Juliet's nurse.

See this show. Laugh yourself smart.