Harry Potter and the Cursed Child review: adult angst and a magical, theatrical coup

"Keep the secrets" is the injunction on badges handed out as we leave the theatre. It's a motto that makes life hard for us hacks, but I am happy to divulge that John Tiffany, as director of this pair of two-and-a-half-hour plays, has masterminded a thrilling theatrical spectacle.

It is also one that will make much more sense to hardened Potterheads than to anyone who is not a member of the global cult. What we have is a brand new work by Jack Thornebased on an original story by himself, Tiffany and JK Rowling: a venture that I approached in a state of benign semi-innocence. I've read one of the seven Potter books and seen a couple of the eight films, and enjoyed them without becoming an addict. At times during the day, I felt as if I had wandered into Henry VI Part II without having seen the preceding plays.

I relied heavily on the expertise of my 11-year-old grandson, who was able to explain to me the intricacies of a Triwizard Tournament, sat enraptured through the day and who made a basic critical point: “If you’ve read the books, you’ll get more out of the play.”

But what can one safely reveal? It is no secret that the story starts where the seventh book leaves off. Harry (now 37) and Ginny, accompanied by Ron and Hermione, watch as their offspring set off from King's Cross for a new term at Hogwarts. This is the cue for the first in a remarkable series of wonders by in-house illusionist Jamie Harrison, where the conventionally clad kids magically acquire school uniforms.

It is also clear that the story is going to take an unusual turn. Harry's son, Albus, is an isolated, unpopular kid living under the shadow of a famous dad. His one true friend is Scorpius Malfoy, the son of his father's arch enemy, Draco. But is Albus, as Harry suspects, an innocent dupe? And is there any truth in the rumour that the blond Scorpius, who looks like a thinner, adolescent Boris Johnson, is really the child of the dark wizard, Lord Voldemort?

The two plays rely heavily on a knowledge of the fourth book, The Goblet of Fire, in which Cedric Diggory was killed during the Triwizard Tournament and Harry escaped. But what struck me was how Thorne, like Rowling, knits together a series of mythical strands. There is the quest motif, which is as old as Arthurian legend. There is the idea of time travel, which has been a standard part of sci-fi from HG Wells to Doctor Who. On top of that you have a Manichean world in which good and evil are locked in perpetual combat. Underlying all that is a mix of white magic and Christian theology that leads Harry to say, at one point, “A child died to save the world.”

If Thorne has added yet another ingredient to an already complicated brew it is that of post-Freudian guilt: much of the story revolves around the adult Harry’s angst at his past actions and Albus’s need to prevail over his father. But, just as things start to get a bit heavy, Thorne adds a touch of leavening humour and reminds us that a smile is as good as a myth. At one point, Scorpius reminds us, with a smirk of self-congratulation, that “It’s time the Time-Turner became a thing of the past.”

I got as much pleasure from the staging as from the convoluted story. Tiffany and his designer, Christine Jones, have created magic out of the simplest ingredients. The set is dominated by Victorian gothic arches, more reminiscent of St Pancras than King's Cross, and by the brilliant use of suitcases and portable stairways. An exciting escape on top of a moving train is evoked through a line of luggage and the estrangement of Albus and Scorpius is suggested by flights of steps that move as nimbly as Fred Astaire. Harrison's magic, Katrina Lindsay's costumes and Neil Austin's lighting achieve triumphant fulfilment in the creation of the Dementors, dark forces who suck the souls out of humans and who float through the air like wraiths.

- Guardian service