“Work, more work and six foot of earth in the end. That’s life,” says John Rutherford. That single-minded work ethic is what drives him on and drives his family to despair and desertion. As head of the century-old family glassworks business going through hard times (the banks won’t lend money), he bullies his way out of a changing world that threatens his control (“I’ve a right to be obeyed”). But he has a messianic mission to preserve a dynastic destiny at all costs.

I laughed quite a bit going round the exhibition to which the Barbican’s latest theatre events are tied, The Bride and the Bachelors. Pioneer Marcel Duchamp’s 1921 “Readymade” Why Not Sneeze, Rrose Sélavy? is funny in itself: a metal birdcage containing marble sugarcubes with a cuttle bone and a thermometer stuck through the bars.

It's odd that Jerry Herman merits only a passing mention in Stephen Sondheim's two-volume autobiographical take on Broadway words and music, Finishing the Hat and Look, I Made a Hat. In a couple of subjects Herman chose no less daringly than the master. Yet while La Cage aux Folles is now so entrenched that we forget its original boldness in asserting a loving gay relationship, Dear World's eccentric mix of eco-plea and nostalgia has yet to be established as a bittersweet chamber piece.

Noël Coward's 1924 play must have been thought very daring at the time, dealing as it does with a young man's cocaine addiction - no wonder it has been called the jazz age's Shopping and Fucking. But young composer Nicky Lancaster's penchant for nose candy wasn't the social transgression being examined - his real addiction is not drugs, but men. Quite how the then 24-year-old Coward (who created the role of Nicky on stage) got the play past the Lord Chamberlain in anybody's guess, but thankfully he did, and its themes still resonate today.

You don’t so much watch a Robert Lepage show as surrender to it, and his latest project sees Canada’s most innovative theatre-maker in full assault. It’s hard to think of another director whose response to the Iraq War would involve an Elvis impersonator, menopause as a major plot point and a visual cadenza for twelve perspex chairs, but that’s the love/hate thrill of Lepage. Spades is the first in a planned tetralogy of plays each themed around one of the suits of cards.

In a draining first work, Ailís Ní Ríain infuses a coming-of-age saga with Irish folklore. The outline sounds gripping enough: burdened with caring for their ill parents, two teenage friends run away to the Irish coast. But then come cultural threads that weave uncomfortably into the canvas, plus surreal overtones that suggest the story is not so straightforward. On their journey, the two girls meet a loopy farmer, a loopy lorry driver and a loopy butcher, who tell them a fairytale about a lazy girl who would prefer not to spend all day behind a spinning wheel.

When's the last time you encountered a play with a hissable anti-hero and a young heroine who radiates charity, decency, and all things good? Those polarities are on full-throttle view in The Stepmother, the all-but-unknown Githa Sowerby play from 1924 that makes up in its vigorous appeal to the jugular what it may lack in dimension and subtlety (Chekhov this ain't.) And if the opening night is any gauge, Sowerby's tale of a young wife and her unctuous, much older rapscallion of a husband has a demonstrable capacity for evoking responses from the crowd.

There’s nothing novel about novel-adaptations on stage. We’ve seen every classic from Pride and Prejudice to Tess of the D’Urbervilles, The Woman in White (and The Woman in Black) get the full theatrical treatment, and I’m not sure any have ended up the better for it. The power of a tale is in the telling, and unmoored from the delicate narrative handling of an Austen or a Dickens things can go horribly awry.

Last weekend it was the 50th anniversary of an important event in postwar Welsh history. In early February 1963 the Welsh Language Society – Cymdeithas yr Iaith Gymraeg – protested for the first time about the right of Welsh speakers to live their lives in Welsh. At Pont Trefechan in Aberystwyth 500 people gathered on Saturday to mark the event and the same number came back on Sunday to Y Bont (The Bridge), a commemorative outdoor play devised by the Welsh-language National Theatre, Theatr Genedlaethol Cymru.

A little man takes on Authority and fails. A little man dons a colourful uniform, complete with boots and spiked helmet, and he becomes Authority. Carl Zuckmayer wrote Der Hauptmann von Köpenick in 1931, two years before Hitler came to power.