Dementia is an increasingly common theme in theatre, television and film. But although there are plenty of stories about old people suffering from Alzheimer’s, what does it feel like to experience this condition? French playwright and novelist Florian Zeller’s Molière Award-winning play – transferring to the West End after highly praised runs at the Tricycle Theatre in north London and the Theatre Royal Bath – attempts an answer by using a sophisticated structure and a deliberately ambiguous method of storytelling.

I never thought I’d be a writer. Writers are people with something to say, big ideas, agendas. I was a director, through and through. I love working with actors, playing with music and text, thinking in three dimensions. The solitary confinement of a writer’s life filled me with dread. And so I spent a very happy eight years directing before I wrote my first play, Blue Stockings (pictured below by Manuel Harlan), and needless to say, the writing of it took me completely by surprise.

Welcome back Martin McDonagh. It’s been more than 10 years since you’ve had a play on in London, and I was beginning to think that we had lost you to Broadway, and Hollywood, for ever. As you know, I loved it when your Leenane Trilogy burst onto our stages in the late 1990s, and although I wasn’t that keen on some of the follow-ups, your The Lieutenant of Inishmore (2001) and The Pillowman (2003) are among my favourite plays.

With the election of lefty outsider Jeremy Corbyn to the Labour leadership, are we entering a new era when upsets and surprises have become a new way of life? Is it really true that anything is now possible? As if to engage with these pressing questions, Tanya Ronder’s new play is all about how a perfect family is suddenly visited by some totally unexpected events. What starts with a dodgy doorknob escalates over 90 minutes into a full-scale domestic breakdown.

We all know what the word “addict” means, but what does it feel like to be one? Thirtysomething Emma – a minor actress played with immense conviction and quirky charm by Denise Gough – knows exactly. At one point in Duncan Macmillan’s engrossing new play, she says, “People who aren’t addicted to anything are really missing out, you know?” For the addict lives a life of glory: they feel complete, and loved and satisfied. Yes, that’s it. They love their addiction – and their addiction loves them back.

We’ve not been short of memorable London productions of Arthur Miller’s best known works. Ivo van Hove’s triple Olivier award-winning A View from the Bridge, which transferred to the Wyndham’s Theatre from the Young Vic earlier this year, and the Old Vic’s The Crucible, directed last year by Yaël Farber, were two exceptional productions. And now we have the seminal play of the 20^th century. The RSC’s Death of a Salesman arrives from its short run at Stratford garlanded with plaudits, but it’s even better in this West End transfer.

That the truth will always be so much bigger than we can comprehend is something I had to accept as I started to write Oppenheimer. There are so many sources, so much information, so many hundreds of books, declassified files, interviews and history. One biography of the man took its authors 25 years to write. And there are still the hidden thoughts that were never written down, conversations long forgotten by people now long dead. There have to be so many omissions that it is an impossible task to tell this "truth" over the course of one evening’s entertainment.

When writers research, it’s not all about digging for facts. Feelings also count. When Nina Raine spent three months visiting hospitals for a play about the medical profession, she found a strange feeling spontaneously erupting inside herself. “The funny thing is I was getting up early for me, 6.30, to get on a bus to be at the place by a quarter to eight and I just started within a week to feel like a put-upon doctor saving people’s lives. Don’t these people realise I’m going to hospital? You do start to get this God complex.”

Fresh from global domination with The Curious Incident of the Dog in the Night-time, currently garnering rapturous reviews on Broadway, inexhaustible playwright and adaptor Simon Stephens has swapped Mark Haddon for Anton Chekhov and a new version of The Cherry Orchard, now previewing at the Young Vic. It’s not his first time bringing late-19^th-century work to the venue, having enjoyed enormous success with A Doll’s House in 2012, but it is his first time tackling Chekhov, who he readily professes is his all-time writing hero.

A still Sunday morning in late October… the sky monotone grey… my friend and I are on a fact-finding mission in Jackson, Mississippi. We drive to the outskirts of the city, take a left onto Hanging Moss Road, and see ahead of us, in isolation among the pines, the Word and Worship church where Bishop Jeffrey Stallworth will be conducting morning service. For the next two hours I listen to the words and music which will, five years later, form the basis of my thinking for Perseverance Drive.