Published in 1915, John Buchan’s The Thirty-Nine Steps has had a rich life post publication, with several adaptations including an acclaimed 30s version by Alfred Hitchcock. It’s a strong text, one that follows Richard Hannay, an archetype British hero, as he finds himself falling into a spy tale that takes him up to Scotland and into the world of secret agents, murderers and devilish twists. One can draw much comedy from this and the version that tours to Oxford is not even the first comedic take on it. But it is, arguably, the very best.

Patrick Barlow’s adaptation feels like it hasn’t aged a minute since it opened 18 years ago and is still wonderfully capable of astounding and enthralling. From an early guffaw that rippled through the audience when Richard comments on newspapers being full of election news (I wonder why that speaks to us so much right now), laughter is a near constant soundtrack to this production, a joyful two hours of theatre.

A core quality is boiling the production down to a cast of four. Tom Byrne is a charismatically ridiculous lead and (sort-of) straight man and Safeena Ladha makes an impression in a series of potential love interests for Richard. But much of the production is stolen by the pair of Clowns who take on the rest of the parts, often within the same scene. Eugene McCoy and Maddie Rice do terrific work, changing their voice and physicality at whip-smart speed. They comfortably play dastardly villains, lewd businessmen, figures who help and hinder Richard on his journey. The coup of putting this all on four performers is that The 39 Steps never really has a moment to stop and breathe. It is, in fact, a slight disadvantage that the production has an interval, as it stops the momentum that builds in its track and the early portion of the piece’s second half must work to regain it.

And while this is a night that moves at a terrific pace it doesn’t sacrifice theatrical innovation. Props whip on and off stage, are used for the use intended and not. Visual gags abound, with even costumes being a prop used to show the environment around them. There are moments of terrific shadow puppetry that are used to give the work an epic sweep and this is a real thrill ride. The stage managers joined the curtain call and feel as important as the actors we see on stage.

In its 18 years it feels like the vim, vigor and innovation of The 39 Steps has inspired other terrific works of theatre. Its DNA can be seen in the likes of Mischief Theatre’s The Play That Goes Wrong and the Operation Mincemeat musical. And as brilliant as those works are, there is still so much to recommend in the production that started it all. As we left the Playhouse and overheard the dizzying praise the audience had for what we’d just watched, I couldn’t help but dwell on the fact that it’ll be tough for there to be another evening in an Oxford theatre that can be just as much fun as this one. I strongly recommend you find time this week to take in this Hitchcockian treat.