There are very few comedy vehicles entirely suitable for the unique, insane genius of Charlie Chuck: but in Nudge writers Chris Lince and Matt Holt have made a damn fine attempt.

What is even more surprising, given that the role of the barmy, paranoid, filthy tramp of a neighbour so perfectly suits Chuck's twitchy, barking persona, is that the part wasn't originally written for him.

Holt and James Lamont play the straight men in all this, even though they are hardly what you would call well-balanced themselves. Comedy obsessive both, they believe that stand-up stardom is their destiny, despite the minor handicap of not having performed it for three years since their humiliating defeat in the Masonic May Day Mirth Match competition.

So they strut around their flat ­ and this is one of the few Fringe shows with a proper set ­ drafting routines which they carefully file away, never to be used. They perform this with an unnatural showy energy, with a rhythm and overplayed level of performance that takes a little getting used to.

When Chuck arrives, things take a definite upward swing. He steals every scene, for sure, overshadowing his younger co-stars even when bound and gagged, but keeping him a sideshow rather than the main attraction ensures that his madness has some context and exploits it for joyous effect.

And things get better still when the fun comes to rely less on the so-so script, and more on the action. There's an inventively stupid montage sequence ­ or Lamontage as they're wont to call it ­ showing the passage of time as the pair prepare Rocky-style for their big showdown; and a silly chase sequence with axes and placards is rich in high-energy slapstick.

This lively comic spirit, and the delight that is Charlie Chuck make Nudge worth a look, even if it doesn't quite hang together as the comic play it aspires to be.