Theatre review: And the latest of these is Love

There is only one place where the mythical figure of Charon might steer his boat along the same stretch of water as a boat with three chaps and a dog in it. Virgil meets Jerome K Jerome: it could only happen in a play by Tom Stoppard.

His latest, The Invention of Love, opens with AE Housman, author of "A Shropshire Lad" and the pre-eminent classicist of his generation, standing on the banks of the river Styx. Some scholars think the Styx was a river in Arcadia. It would be neat if it was: for Stoppard's awesomely erudite and entertaining play springs in many ways from the same source as his last one. It shares with Arcadia (as well as the radio play In the Native State, later staged as Indian Ink) a fascination with the interconnected- ness between then and now, the unreliability of evidence, the haphazardness of what survives.

We first see John Wood as the elderly Housman, in a three-piece suit, blinking at the spotlight, arching a whiskery eyebrow and peering into the gloom. Dry ice swirls around his boots. He reacts well to the sight: "I'm dead then. Good." A memory play that divides its central character into his younger and older self, The Invention of Love tracks back from Housman's death in 1936 to his arrival at Oxford in the late 1870s, cutting between Hades and Oxford, Bayswater, Ealing, Shropshire and Dieppe. Those are only a few of the directions in which the play travels. Time is another, as the conversation shuttles between pagan and Christian societies with the nimbleness of someone flicking channels. The way Housman talks about them, the Sacred Band of 300 Thebans, who died as comrades in arms at the battle of Chaeronea, might have been chaps in another college.

Wood plays the 77-year-old "AEH" with a tremendous mix of pedagogical choler, scepticism and lingering pain. His command of Stop- pard's elaborately structured speeches is masterly: wafting a cupped hand in the air, like a conductor bringing in the wind section for a delicate passage, Wood narrows his eyes and skewers a fellow critic. The play brims with insider knowledge, peppery observation and magisterial insight. Stoppard may introduce all sorts of activities - croquet, billiards, boating, picnics, athletics - but these are mere concessions to the business in hand. Talking. Up here, in this heady stratosphere of learning, Latin and Greek exert a seductive pull. While some playwrights lecture us in the belief that we're stupid, Stoppard lectures us in the belief that we're intelligent.

At Oxford, the young Housman - beautifully played by Paul Rhys as a quivering thoroughbred, a fiercely sensitive and gentle soul - meets Moses Jackson (Robert Portal), an athlete and scientist, who becomes the unrequited love of his life. He also learns about a fellow undergraduate, Oscar Wilde. Stoppard has returned to Wilde, but this time he uses his life as the background for his portrait of Housman.

When Housman comes down from Oxford, without a degree, he takes lodgings in Bayswater with Jackson. They both work at Her Majesty's Patent Office. One question that Housman is not required to deliberate on is who exactly invented love. He could tell his employers (as he tells us) about Cornelius Gallus, whose one extant line puts him ahead of Propertius as the first of the Roman love elegists.

Questions about the love between men - what it is and how our conception of it has changed - are realised in three strikingly emotional scenes. One occurs when the stoutly heterosexual Jackson challenges Housman over whether he is "sweet" on him. Another occurs when Housman meets Wilde (after his release from prison) and the destinies - of the introvert and the extrovert - are vigorously contrasted.

The third occurs when the older and younger Housman sit on a bench in Hades. The red and weathered face stares at the white and translucent one, aware of the grief ahead. Here Housman's second passion is powerfully demonstrated. In an uncompromising defence of textual criticism ("the crown and summit of scholarship"), Wood reveals the damage done to a Catullus poem by a misplaced comma. "It's where we're nearest to our humanness," says Rhys, later. "Useless knowledge for its own sake."

Stoppard broadens the social context to include fruity cameos of the Oxford intellectuals Ruskin, Jowett and Pater (seized with relish by Benjamin Whitrow, John Carlisle and Robin Soans), who play croquet and pronounce on art, education and morality, and the London journalists Henry Labouchere, WT Stead and Frank Harris (the same actors, the same relish), who play billiards and pronounce on newspapers, sex and morality. If the joke quota in this mature, impassioned play is stricter than you might expect, the aphorisms are in full flow ("biography is the mesh through which our real life escapes", and so on). Anthony Ward's set of tall library shelves with grey leather-bound tomes acts as an oblique tribute to Stoppard's voluminous research. The Invention of Love is Richard Eyre's final production as director of the National. This week - and it could have been other ones - four of the "Five Best Plays" recommended on the Going Out page are on at his theatre. We've been very lucky.

The story behind the musical Maddie is as appealing as the musical itself. It opened in Salisbury to rave notices , but failed to transfer. The Daily Telegraph's critic told his readers and they responded with pounds 150,000. Last week it opened in the West End. In another musical developed out of workshops with Stephen Sondheim (a genre I'm becoming wary of), Nick and Jan move into a dilapidated San Francisco apartment and discover it is haunted by a 1920s dancer, Madeleine Marsh. She takes over the body of Jan - both roles played by the radiant American newcomer Summer Rognlie - and Jan now has the chance to do something about her "nothinglife".

Maddie isn't terrible. It has clever-enough lyrics by Shaun McKenna, one of those just-what-you-might-expect showbiz scores from Stephen Keeling, and a book (McKenna and Steven Dexter) that mines similar themes to the Donmar's Sondheimesque Enter the Guardsman: stale marriages and having sex with your partner while thinking they're someone else. You need to be Sondheim or Peter Nichols to jolt us with an insight about marriage: Maddie approaches it through the tired conventions of musical comedy.

The Comedie Francaise returned to London for the first time in 25 years to open the French Theatre season with a cooly passionate production by their artistic director Jean-Pierre Miquel of Marivaux's psychological comedy Les Fausses Confidences. Miquel's semi-abstract set of a curving wooden wall and billowing curtain carries unfortunate hints of a car showroom. But elsewhere in this immaculately poised production, as the penniless young lawyer Dorante attempts to win a wealthy young widow, Araminte, the deceptions, shifts in status, and unexpected blossoming of relationships are made impressively clear. To see the elegant Comte (Andrzej Seweryn) seated at the table, with shiny shoes and white button-hole, with one hand on his silver-topped cane, the other holding a glass of red wine, is to be reminded of something crucial about playing Marivaux. It isn't gulp, gulp, gulp. It's sniff ... sip ... sniff ... sip ... sniff ... sip. The distinctions are exacting.

'The Invention of Love': Cottesloe, SE1 (0171 928 2252). 'Maddie': Lyric, W1 (0171 494 5045).