Noel Coward’s Blithe Spirit appears to be a harmlessly escapist cream puff. It’s the story of a remarried widower, a writer, who, as research for a character in his next book, invites a medium to his well-appointed home to perform a seance. The seance is far more successful than anyone expected, and brings the ghost of his late first wife back into his life, where she wreaks hilarious havoc with his second marriage.

The possibilities for comedy are obvious, and, in the current Stratford production, exceptionally well-exploited. Ben Carlson’s chronic dyspepsia perfectly suits the disposition of the writer, Charles, and Michelle Giroux’s slinky lynx-like Elvira, Charles’s late wife, is the perfect creature to discomfit the primly chirping and agitatedly squawking Ruth, the bird Charles is currently married to, played by Sara Topham. Crowning the central quartet, Seana McKenna makes for a hilarious Madame Arcati, the medium, precisely because she creates an actual character rather than a stage eccentric. She’s full of wartime can-do; she might as well be wearing a t-shirt that reads, “Keep Calm And Try Another Seance.” Everyone’s timing is spot-on; the set (by Simon Higlett) looks practically edible – the whole show is a delight, and director Brian Bedford can add another Coward-ly notch to his well-notched belt.

But this play is really a very ugly piece of work when you stop to think about it, positively Seinfeldian in its misanthropy – and in its misogyny.

It’s Charles’s own wife, Ruth, who describes him as “hag-ridden,” and, indeed, every female character in the play is in some way appalling. Madame Arcati is not only incompetent but utterly self-involved; and she gushes over the ghost she conjured like a teenage girl meeting her boy band idol. Elvira, worst of the lot, is a murderous narcissist, and Ruth is a gimlet-eyed drill sergeant. Even the minor characters – the spacey maid, Edith (Susie Burnett), and Mrs. Bradman (Wendy Thatcher), wife of the neighborly doctor (James Blendick), are figures of contempt. We don’t really notice this while the play is on, because we’re too busy laughing. It’s only later that we realize what we’ve been laughing at.

Charles, meanwhile, is the truly Seinfeldian figure. He quickly gets over his initial alarm at the return of his late wife, and comes to delight in the opportunities both to bask in her adoration and to drive his current wife to distraction (Ruth is thrown continually on her back foot because only Charles can see and hear Elvira). His pleasure is entirely cruel, and grows more so when we see him more put out than distraught at Ruth’s untimely demise (Elvira kills her by accident, aiming to murder him so he can join her in the next world). Like the characters on “Seinfeld,” Charles sees himself as the superior victim of a world of idiots, but (also like the people on “Seinfeld”) is himself a character utterly without love or sympathy or any emotion beyond petty egotism. And his ultimate triumph is not the defeat of the common and sentimental mass of humanity, and communion with a sparring partner who shares his worldliness and his superior wit – a common happy ending in Coward – but the achievement of splendidly snarling isolation.

It’s very funny. But it’s not funny in the more familiar Coward mode – there are few quotable witticisms, and little revelation of the deep needs of the meticulously armored self that you get from Private Lives or Present Laughter or – especially – “Brief Encounter” and its theatrical precursor, Still Life. The spirit of this play is far from blithe – it’s a veritable poltergeist. I wonder what animated its creation, and what animates the audiences who delighted in it during the dark days of World War II, and who continue to do so, giving this play, with its very dark picture of human nature, the reputation of being one of Coward’s lighter works.

Blithe Spirit runs on the Stratford Festival’s Avon stage through October 20th.