Donmar Warehouse, London WC2
Polar Bears is a thoroughly depressing night at the theatre, and I mean that in a good way. Its thoroughness is a splendid thing. The case this new play makes for the pointlessness of life is coruscating, brilliant and exhaustive.
To say that most of us will leave this intense 90 minutes - broken up by laughter that dies on your lips - and within minutes find our spirits lifted by a glass of wine and a meal is not to be snide about Mark Haddon's work any more than it is to belittle Endgame or King Lear. That's the power of theatre: even at its strongest, it is relatively weak.
Besides, a good play, however pessimistic, is always nourishing. It begins with a scene designed to wrong-foot. John, a hirsute philosophy lecturer played with great range and sureness by Richard Coyle, is talking to his brother-in-law. Sandy seems well disposed towards him and reluctant to believe the bad news that he has to deliver: namely that he has killed his wife, Sandy's sister Kay. (The audience wonders whether to laugh and thinks better of it.)
One's assumption is that this story is about John's madness and that Sandy is a counterpointing voice of reason. But the plot is essentially the story of John's relationship with Kay and of her - not his - bipolar disorder. Its punch-line, which comes in the beginning scene, is not only that insanity is hereditary - Sandy is far from rational but a disturbed and, in Paul Hilton's rendition, almost manic figure who as a child found his father's dead body after his suicide - but that it is infectious, to be passed between loved ones. Worse, suicidal depression may be a rational response to life.
Central to all this is neither Sandy (whose part is slightly underwritten and fizzles out) nor John (whose part isn't and doesn't), but Kay, played by Jodhi May, who fills her character with the intense charm of a depressive in an upswing. Kay is creative, imaginative, a brilliant storyteller - and these qualities are sexy and seductive - but she is also a fantasist. She tells Richard she has a publisher for her illustrated children's book.
Later she says it has won the Carnegie Medal (for which Haddon's The Curious Incident of the Dog in the Night-Time was shortlisted). In fact, as her mother (Celia Imrie at her creepiest) almost gleefully explains to John, she cannot draw at all. Her poetical speeches of wonderment about the universe, although beautiful, are equally fantastical.
Her troughs, however, are deep in both senses, sometimes delivered with the help of a jovial Geordie she meets in a mental hospital who thinks, or who she thinks, is Jesus and certainly dresses that way. His Sermon on the Mount - a tour d'horizon of the worst of human nature - concludes: "It really will end in the basement with tinned fruit and the cans." He returns later with a show-stopping lecture, illustrated by a corpse wrapped in polythene, on how it ends for the human body: "Stage three, black putrefaction, starts around day ten . . ."
This, he tells John, is all the heaven there is. When, near the end of the play, John addresses his students with his customary beginning-of-term turn on the history of western philosophy, it falls apart: "It all ends in the basement and I really do not think the goddess of wisdom is going to intercede at the last moment."
The play, briskly directed by Jamie Lloyd against Soutra Gilmour's stark sets, is told in a fractured time scheme, so you have to work a little to reassemble the narrative. It proceeds also by shifts of theatrical tone - relatively naturalistic scenes followed by monologues, the most effective of which I have already mentioned.
The most trying is a grim fairy story delivered by Kay almost as a slap in the face to those expecting Haddon to write something child-friendly. Its main purpose is to hold up Haddon's slightly fragile metaphor contrasting the giddy aerial perspectives of madness with the basement in which Kay's body - and ours - will decompose.
The polar bears of the title, incidentally, come from John and Kay's daughter's dream. I'll warn you now, there is nothing the least bit cuddly about them.
Andrew Billen is a staff writer for the Times