Benet Brandreth, Soho Theatre

Storytelling, they say, is an almost lost art. Well, not while Benet Brandreth is around, it's not. Brandreth, Sandhurst graduate and a lawyer by day, studied Philosophy at Cambridge and has packed rather a lot into his life, real or imagined. He weaves a fantastical tale charting his story from graduation to last year - when, not for the first time, he saved the life of a member of the royal family.

He comes on stage in a dinner jacket and places his handgun on a table, explaining that if No 10 calls he may have to steal away. What follows is an often surreal flight of fancy, an hour-long shaggy dog story of derring-do, fighting monsters and saving the nation.

There's a laugh in almost every line, delivered in Brandreth's rich actor's voice - and in case you're wondering, yes he is the son of Gyles, a fact he gets out of the way early on, telling us that his education was the finest that 20 years of appearing on Countdown could buy. It's no surprise, then, that this is a determinedly clever show: The Brandreth Papers is full of biblical and classical illusions, alongside knowing references to popular culture. Thucydides makes an appearance, as do the lesbian semiotics of Dick and Jane books and Brandreth's teenage Dungeons & Dragons habit.

Brandreth is a gifted raconteur and, as tales of mock heroics go, you won't get finer

Brandreth places himself, Zelig-like, at the centre of historical events. And so we learn that after graduation he lost his great love, Jane, after a misunderstanding about what he thought was an offer of a threesome and so, with his chiselled good looks, he went to try his luck in Hollywood. That was working out fine until he was filming in Hong Kong during the handover to the Chinese and there was an unfortunate incident on board the royal yacht, involving Prince Charles (whose life he saves using a rolled-up copy of GQ), Demi Moore and an enraged Bruce Willis.

Years later and he's saving Prince Philip's life, a feat involving a rolled-up carpet this time, in a wonderfully ridiculous scenario full of ornamental detail and in which Jane is involved again. It's all delightful nonsense, and essentially a knight's tale of boy meets girl, loses girl, meets her again, loses her again, and then meets her again when honour wins the day.

This is a beautifully crafted set and one that I enjoyed greatly when it was at the Edinburgh Fringe. But labouring, as we all were, in the ridiculous heat of Soho Theatre's studio and with a polite rather than enthusiastic audience, it felt as if some of his energy had been sapped and this format's one limitation was exposed - this is not a show where a quick spot of “and what do you do?” to the front row is going to throw up a comedy nugget to display the comic's quick wit or change the pace a little. By its nature this is a tightly scripted hour, although Brandreth did manage the occasional throwaway line about the heat, and he has also worked in some smart current references to donor dinners and the petrol "crisis". But he's a gifted raconteur and, as tales of mock heroics go, you won't get finer.

• Benet Brandreth is at Soho Theatre, London W1 until 31 March