A Soldier in Every Son - The Rise of the Aztecs, Swan Theatre, Stratford-upon-Avon

What might have proved a ground-breaking collaboration between the Royal Shakespeare Company and the National Theatre of Mexico proves instead to be a lost opportunity at forging a South American “Wars of the Roses” epic.

At once too short and too long - a proposed Aztec trilogy by Mexican writer Luis Mario Moncado has been condensed into one exceptionally tedious three-hour play- the production rapidly becomes a repetitive procession of chaps in helmets and cochineal tattoos, with names containing far too many x-es, fighting each other on the too tiny plains of Texcoco in the early 15th century.

The prince of the Acolhuas resists his arranged marriage, causing havoc among the Tapenecas, who then go berserk among the Azteks while Itzcoatl, great king of Tenochtitlan, sorts out Maxtla and Tacuba before Nezahualcoyotl, son of Ixtlixochitl, is reunited with his mother, mad queen Mayahuel, daughter of Huitzilihuitl, who thinks that he, Nezahualcoyotl, is her husband.

Uncrossing my eyes after writing that sentence, I must admit that the dynastic upheavals are insultingly simple on the stage, which becomes a playground for a mini-Mahabharata with distant echoes of Peter Shaffer’s The Royal Hunt of the Sun in neighbouring Peru later on.

But whereas Shaffer concentrated on the philosophical conflict between the Spanish and the infinitely more pronounceable Inca sun king Atahuallpa, Gary Owen’s up-and-under version of Moncada’s play just seems like one damned thing after another.

The tribes form an alliance after the sacrifice of a boy king – cue knife plunged in blood sack helpfully situated near boy king’s right hip – and the warrior in stubbly shoulder pads who owns an avocado farm but looks like a pineapple intones the invocation.

An invocation to, or about, what, I’m not sure, but it seemed a good way of ending a show that started with Alex Waldmann’s tribal crown prince painting squiggly hieroglyphics on his slave girl’s belly button.

The decorative parts, as opposed to the speaking parts, are the best thing in Roxana Silbert’s production: aquamarine hair stubble that looks like bathroom tile mosaics; a parched stage curling like a crusty old poppadom with a removable flap; John Stahl’s Cleopatra head-piece that wobbles hilariously whenever he denounces his enemies in four-lettered fury, which is often.

There are some levered in references to Shakespeare’s Henry IV and Julius Caesar, but no language to justify them. Down Mexico way, they swear and brawl like revellers at chucking out time in Sauchiehall Street.

To 28 July (0844 800 1110)