The Lightning Thief: The Percy Jackson Musical - all Greek to me

Percy Jackson is neither the missing one from Jackie, Tito, Jermaine, Marlon and Michael, nor an Australian Test cricketer of the 1920s, but a New York teenager with dyslexia and ADHD who keeps getting expelled from school. He’s a bit of a loner, too intense to huddle with the geeks, too stubborn to avoid the fights with the jocks, and his mother won’t tell him anything about his absent father. Who turns out to be a Greek god. Could happen to any kid. 

It’s that blend of familiar anxieties and fantastical backstory that propelled Rick Riordan’s bedtime stories into novels, films, games and, ten years or so ago, a Broadway musical that has its UK premiere at The Other Palace, appropriately on Thanksgiving, given it's American vibe. It’s not entirely fair to label it a kids’ show, though it does shoot towards the younger end of the YA demographic, and, as with other products based on existing IP, it will draw in fans eager to see their hero IRL, as it were. The question for the more casual punter or for someone whose patience with YA material expired with JK Rowling’s sense of humour at about Book Five of the Harry Potter saga, is whether it’s any good as a self-standing piece of theatre. Spolier alert – it isn't.We open with “The Day I Got Expelled” and, after swallowing great wodges of exposition to locate Percy socially and psychologically, we heave a sigh of relief and look forward to the epic quest, the mythical monsters, the deathly dangers. To be fair, we do get a bit of that (a beautifully constructed minotaur, spectacularly staged by choreographer Lizzie Gee on her debut as a director is a highlight) but, by the first act closer, “Killer Quest”, we’re still stuck in exposition purgatory as the lost boys and girls sing of their hopes and fears. Pace is everything in family-oriented shows and this production progresses like a slow turning kebab grill.

Impatience turns to irritation after the interval, when Joe Tracz’s convoluted and confusing book conjures train tickets from squirrels, a motorcycle that can seat three pillion passengers and a bag of gold coins from a trio too poor to afford food a day or two earlier. 

Percy, Grover and Annabeth’s trek across America to The Underworld (located in LA, natch) has echoes of Stu and Frannie’s journey to Las Vegas in Stephen King’s The Stand but little of the jeopardy and none of the psychological depth – do these kids learn anything from their trials? Maybe we’re sated by CGI-saturated movies or maybe it’s the need for the plot to include beheadings while tagging the show as suitable for ages 8 and above, but the outcome is violence that’s very vanilla, for all the swinging swords and jabbing daggers.

And the songs? Rob Rockiki can write a rock-pop footstomper and give a number to the impressive Paisley Billings to belt out at the gates of hell (“D.O.A.”), but there’s a generic quality to the melodies, one tune merging into the next, one voice indistinguishable from the other. It doesn’t help that any hint of a romantic relationship between Percy and Annabeth is so coyly presented as to be positively subterranean and our hero never really moves on from his daddy issues. Perhaps because many in the audience will know that Percy lives to fight another day – indeed, many other days – theatre’s alchemical marriage of music and drama that leads to catharsis never arrives, a succession of crises swept aside almost before they’ve had time to register with us. There’s precious little wit or humour either, a shame as “The Campfire Song” is funny, teens articulating exactly why they don’t get on with parents. It's an hour before the next chance to laugh – when Percy's parents eventually meet again.

Despite the lacklustre score, a somewhat confusing book that scrolls through Greek gods and heroes’ nemeses at a dizzying rate, the cast are winningly charming. Max Harwood (pictured above) has exactly the right kind of non-threatening good looks and demeanour Percy needs, not a conventional teen heartthrob, but vulnerable and angst-ridden – not smiling once that I can recall in two hours on stage. Boys and girls will identify with his hesitancy and his pain. 

His two chums fall four-square into types we know, Scott Folan all sweet-natured generosity as best buddy Grover, and Jessica Lee feisty and fearless as the insecure Annabeth. Amongst the rest of the multi-rolling cast, Samantha Mbolekwa makes the most of tomboy Clarisse with some powerful vocals and both Joe Allen and Greg Barnett take the licence granted to go wildly over the top as a host of grotesque/useless, pantoish parent-substitute characters. 

Short of the crossover appeal that Spirited Away and My Neighbour Totoro recently brokered into huge successes on the London stage, The Lightning Thief: The Percy Jackson Musical works best for the tweenie fans of the franchise and for those who remember when they once were. For the rest of us, it makes us look back on Jason and the Argonauts and Clash of the Titans with an unexpected new respect.

• The Lightning Thief: The Percy Jackson Musical at The Other Palace until 2 March    
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