The 2,000 Year Old Man, JW3

Well, here’s an interesting endeavour. The 2,000 Year Old Man was a series of improvised sketches performed in the 1960s by Mel Brooks and Carl Reiner. Brooks played the old guy, talking about all the great names in history – Jesus, Joan of Arc, Napoleon and many more – he has known in his long and eventful life. Reiner was the straight man, lobbing the questions that Brooks would then riff on.

The humour, which is Yiddish, world-weary and overly dramatic – I am a massive fan – came straight out of the Borscht Belt, a postwar comedy circuit in the Catskills summer resorts in New York State, which spawned not only Brooks and Reiner but any number of Jewish comics, including Jack Benny, Woody Allen and Joan Rivers. (A Catskills resort is also, incidentally, the setting for Dirty Dancing.)

Now Kerry Shale has fused some of the material and created a one-hour show in which he takes the Brooks role and Chris Neill that of Reiner. But instead of them performing their own version of the work, they each have an earpiece with the recording playing in their ear so, they say, they can recreate every cadence of the original – as in verbatim theatre pieces.

Shale and Neill are talented performers, but this format never allows them the chance to shine

It's a strange decision because it leads to a noticeably edgy (and not in a good way) performance – a long way from the delightfully freewheeling sketches that Brooks and Reiner created, many of them just to entertain themselves and their fellow comics before they committed them to vinyl. It's a real shame as both Shale and Neill are talented performers, but this format never allows them the chance to shine.

And when, as happened on the night that I saw the show, Shale's tape failed, they were stuffed. Actually, it was the only point in the evening where Shale and Neill appeared relaxed and joked around on stage; as a technician adjusted his receiver, Shale (still in character) did his own riff about kiboshing it so she would have to touch him. For the first time it felt like Mel Brooks and Carl Reiner had entered the room.

The material, thankfully, doesn't fail. The 2,000-year-old man knew Jesus – “Was he ostracised? He was circumcised!”; Robin Hood “stole from everybody”, and he had a relationship with Helen of Troy's not-so-attractive sister, Janice (“She had a body that could launch a few canoes”). There's some wonderful kvetching, too – he has 42,000 children but "they never visit", and even a mention of his brush with the Spanish Inquisition long before Monty Python got there.

Even if the set-up doesn't quite work, it's good to be reminded of some timeless comedy by two masters of the art.

• The 2,000 Year Old Man is at JW3, London NW3 until 22 March