At the Peacock Theatre, London until Feb 26th.

Old Grandfather! Drunken Uncle! Fierce Father! Dangerous Guy! Cute Girl! Fighting Mother!

No, not the candidates for the Liberal Democrat Party Leadership, nor are they the line up for this summer's Big Brother - they are in fact the characters from the martial arts comedy spectacular Jump, showing at the Peacock Theatre in London.

I was lucky enough to be sitting front row centre for this, and although it meant I had to help Even Older Grandfather onto the stage a couple of times, it also meant I could see just how hard this Korean group were working to entertain us.

There is a small plot, of sorts. The first act concerns regular family training, with martial arts contests and weapon practice, with a little bit of a romantic sideline between Dangerous Guy (who is Geeky Guy when he's wearing his glasses, of course) and Cute Girl. Invariably, mistakes, misunderstandings and plain old family rivalry conspire to prevent everyone from looking quite as cool as they should (Drunken Uncle being a particular master of taking the mickey).

The second act opens with two burglars breaking onto the set from the back, and the ineveitable fight that breaks out when they are discovered. Fortunately, it turns out that they can do martial arts as well, and even the presence of a handgun is not enough to stop Old Grandfather (eventually) leaping into action to save his family.

This is one heck of a show. The precision is amazing - Old Grandfather at one stage leaping a table to catch someone's leg in movement with his cane. Several of the other routines include some very close work with various weapons and pratfalls - although it's advised that Drunken Uncle should not be on stage with a hangover. He works best as the deliberate knowing comedy character, ready to subvert your expectations of how things should go.

Despite being a martial arts extravanganza, this show is extremely funny. Characters at no point take themselves too seriously - from Fierce Father following a great routine with a dismissive camp handwave to the transformation Geeky Guy goes through every time someone takes his glasses off and he becomes Dangerous Guy (cue much shirt ripping and so on). Every detailed sketch has several running jokes - I particularly enjoyed the second half, in which jokes were set up early on and left for, in some cases, around half an hour just so they could add to the hysterical proceedings later.

The physical conditioning of the participants is also incredible. For the very final finale, we are treated to a mix of weapons performance, gymnastics and follow-that! competitiveness, with a blacked-out stage showing only five glowing bo-staffs as they are spun and thrown. The final pose shows all the actors breathing extremely heavily, but you can't spot an inch of fat on them.

This Korean martial arts theatre company were a hit at the Edinburgh Festival and a hit last night - long may this show continue. Unfortunately, it only runs until next weekend, but if you can get a ticket, do so.