An advert for The Valley – latest edition to the reality TV bandwagon – got me thinking about today’s fascination for the grotesque, both imagined and real. But this fascination isn’t new at all. For centuries (and maybe even millennia) man has always had a morbid desire for those things that he finds unpleasant: things we love to hate. Testing the limits of what we can stand.

Now it is loud-mouthed Chavs and loud-mouthed Sloanes, but then it was soldiers back from battle with arrows through their skull and large portions of the gastrointestinal tract hanging through an open wound. And so Prodo – ex-soldier, now freak-show – goes to painter Galactia’s house so she can study and emulate war’s first hand effects on the human form. And thus begins Howard Barker’s play of violence and fervour, Scenes from an Execution, with Tom Cairns directing seamlessly for the National Theatre.

Artist-genius Galactia is not only a woman well past it, but an unattractive one at that. Masculine in appearance and habits, she is disheveled, bra-less and filthy in a breast-revealing smock. Aware but not phased a bit by her unkemptness, she is confident and witty and awesomely strong. And Fiona Shaw does this magnificent character every bit of justice in her performance.

Barker has created a lover for Galactica in the form of younger man Carpeta, here played by Jamie Ballard. Lesser in character and painting skill as well as years, the two make an unusual and riveting couple: in temperament as well as looks. They seem so wrong for each other and despise each other and drive each other insane. Yet there love is. It’s ugly and imperfect and how we can all relate to harbouring an infatuation for the wrong person.

Interplay between art and politics and between artists, politicians and critics makes for a weighty and (some might say) pretentious and ideas-laden premise. Set it in the sixteenth century and you potentially have a recipe for boredom. Scenes from an Execution eschews all those things. It is quick-witted and maintains  a brisk momentum – no sign of the “slumps” that plague many plays – stimulating heart and feeling maybe even more so than our intellectual faculties.

My craving for some Phlip Ridley-style blood and gore was amply satisfied by the vivid realisation of Galactica’s painting of the Battle of Lepanto – commissioned by the state to glorify the Venetians’ slaughter of the Turks in 1571 – through snippets of the Sketchbook’s – played by Gerrard McArthur – detailed description of what populated the imaginary canvas. The Sketchbook is the very notion of abstruse art analysis in human form. There he sits, bespectacled in his brightly lit box, hovering over the action and offering occasional commentary. And later in the play, more fun is poked at affected art interpretation as visitors flock to admire Galactica’s finished masterpiece – some read the brochure and nod with gravitas and others simply weep at the painting’s power to simply move.

Hildegard Bechtler’s design creates the requisite Venetian veneer and gives the production a comforting Shakespearean feel – a feeling also imbued by those immortal ideas of power, politics, passion and tyranny. Peter Mumford’s lighting is immersive. As is his lack of lighting when the Lyttelton’s cavernous stage is steeped in darkness and transformed into the cesspit cell Galactica is encased in when art and artist-lover Urgentino feels threatened by her indubitable power and painting prowess.

Barker, referred to as the “Shakespeare of our time” by the late playwright Sara Kane, may shun the “banality” of comedy – everyone laughing at the same time at the same thing – yet Scenes from an Execution is funny in a morbid and wonderful way. We laugh at their misfortune, at the dry, dark humour and at Shaw and the rest of the cast’s excellent delivery of Barker’s script. For a modern take on Shakespearean themes, go and enjoy Scenes from an Execution before December 9th 2012.