I HAVE been purging my library. Over a decade, I have acquired a variety of interesting books, which I promised myself I would read when I finished writing my latest tome. My reading-for-pleasure heaped itself in picturesque piles on the tables in my study, then filled cardboard boxes, and then plastic crates. The stacks provoked the uneasy memory of Leonard Bast, the hapless clerk in Howards End crushed to death by the weight of his own literary ambition when a bookcase falls upon him.

Fortunately, I recently discovered that you can send books to Oxfam by post. This, of course, is not so poetic as the symbolic purgation by Prospero at the end of The Tempest, when he drowns his book — as I was reminded by Sir Kenneth Branagh, who is back at the Royal Shakespeare Company after a 30-year absence. He is directed by the eminent Sir Richard Eyre, making his debut, unbelievably, at the RSC. It’s a combination so creatively momentous that the King, no less, paid an unheralded visit to the stalls to see it.

Purgation is a perilous business. Some decades back, I decided to clear my shelves of all the playscripts and drama criticism which I had accumulated at the beginning of my career as a theatre critic — a decision much lamented now that my son is an emerging theatre director. But clearing old books to make way for new can free you from the detritus of your past. Volumes of outmoded philosophical critique from university. Once-contemporary books on British politics. Dusty volumes on Irish colonial history. Studies of dead popes. Outdated statistic-filled tomes on world poverty. Amid the prized relics of the past were weeds and tares aplenty.

Shakespeare’s great last play offers a different audit. Fortunately, no video evidence exists of my schoolboy performance as the drunken butler Stefano from a time when my experience of alcohol was even more limited than my knowledge of Shakespeare. But, later, Aimé Césaire’s adaptation for Black theatre, with a capital B, reframed as Une Tempête, offered a parable of colonial oppression from the days when the newly independent African nations offered only the prospect of a brave new world full of goodly creatures.

There are post-colonial underpinnings to Sir Richard’s version, but his emphasis is on Shakespeare’s celebration of a life that is rich and strange, full of magic and paradox. His Miranda is feisty and modern, but gloriously trusting and naïve. Her relationship with her father is loving, as well as challenging. He arranges, and then cannot bear to watch, the blossoming of her first tender romance. There is malice in the manoeuvrings of Naples and Milan, but contemporary politics find a more vivid echo in the Trumpian bluster and braggadocio of the plotting of Stephano and his comical cronies.

Adopting colour-conscious casting, Sir Richard chose black actors for all the islanders: a noble Caliban, a wise Ariel, and the dancers who artfully play the waves, spirits, furies, and goddesses. Prospero’s minions here become his teachers. It is the loving chiding of Ariel which prompts her master’s restorative forgiveness.

Splendidly, Ariel spends the entire play airborne. So, when she is finally set free, she falters in her first liberated steps on land. It is not the white magician who wordlessly comes to her aid, but her fellow indigenous islander Caliban — who now wears Prospero’s deep-blue magical robe, which the erstwhile magus has removed and placed upon the shoulders of his slave. Only then has Prospero truly cast off his past. It is a Tempest for our troubled times.