“The past is a foreign country,” said author LP Hartley – and so too is this musical in comparison to its beautiful source material.

Based on the novel, it tells the story of elderly Leo Colston in 1950 as he reflects on a Norfolk summer 50 years ago when aged 12, he acted as the “go between” for two illicit lovers: upper class Marian Maudsley (the radiant Gemma Sutton) and lowly tenant farmer Ted Burgess (Stuart Ward - who shows off his rather toned torso at one point).

It’s a powerful, and ultimately tragic, story of doomed love, and its complicated time structure must have made it a challenge for Richard Taylor and David Woods to adapt successfully.

But they overcame the hurdle well, with musical theatre legend Michael Crawford as pensioner Leo remaining on stage for almost the entire show as he watches and remembers the three weeks that shaped his future.

Crawford can no longer punch those high notes quite as he did, but his voice is still in excellent shape and he’s the perfect fit for the haunted old Leo.

The staging, too, works well - at once reminiscent of adult Leo’s dusty, overgrown attic, and grand house Brandham Hall in 1900.

The decision to eschew orchestration for a single piano on stage is also masterful, and very fitting for this melancholic story.

It had all the ingredients, then, for an instant classic.

But sadly, it is not, and there is really only one reason for this: the music.

Throughout this 2 hour and 20 minute show, it is impossible to tell when one song ends and another begins. It is all sing-spiel - that dearth of musical theatre.

The one exception is ‘Butterfly’ - a soaring, but repetitive and clichéd number from Crawford as he watches naive little Leo (played superbly by William Thompson on our night) grow in confidence in Marian’s company.

But as the minutes and hours drag on, you can’t help but wonder: why on earth are they singing?

The power of the original story gets you through it, but with tickets on sale for up to £101, my advice would be: save your money.

Rating: 2/5 stars