Not since the Montagues were cast as aliens and the Capulets as humans in the 2000 production of Romeo And Juliet by Malachi Bogdanov and the – mercifully – now defunct English Shakespeare Company have I seen a Shakespeare production so misconceived as Dundee Rep's The Tempest, which is a right dog's dinner.

Shakespeare's final play – in which the blue-blooded Milanese sorcerer Prospero whips up a storm, creating chaos then restoring order, on his Mediterranean island – is certainly open to interpretation, from autobiographical (Shakespeare as Prospero) to imperialist (the "monster" Caliban as symbol of a colonised people). One struggles in vain, however, to make sense of the great rubbish dump, all stuffed garbage bags and abandoned TV sets, which director Jemima Levick and designer Ti Green have made of Prospero's island. An ecological interpretation might suggest itself if the play supported it in any way, but, save the beauty and magic of the island (which the design traduces), it does not.

As is so often the case with poorly conceived productions of classics, one bad decision leads to another. Irene MacDougall's female Prospero is absolutely fine (even if she is referred to as both a woman and a "Duke") – but a female Caliban?! Although much of the ill will which Prospero bears towards the enslaved islander comes from the latter's sexual designs on his daughter Miranda, Ann Louise Ross's Caliban (made to look like a disfigured car-crash victim) is never directed towards the sado-lesbian sub-plot her casting implies.

There is a fine score by Jon Beales and some fine performances, not least from Kirsty MacKay (Miranda) and Keith Fleming (no-holds-barred as the inebriated servant, Stephano). However, the central concept is so overwhelmingly pointless that even the stronger elements are in danger of being submerged in the detritus of Green's ugly set.

If the Rep is staging a mismatch of play and production, Blue Raincoat Theatre of Sligo presents a production of Eugene Ionesco's darkly satirical piece, The Chairs, which is so faithful to the original that one might think it had been directed, not by the excellent Niall Henry, but by the Romanian master himself. It is a fine example of his work, which sits between the abstract existentialism of Samuel Beckett and the politicised surrealism of Alfred Jarry.

In the play, an elderly couple (known only as Old Man and Old Woman) assemble ever more chairs for a non-existent audience who will hear an invited orator speak on the Old Man's world-changing intellectual discoveries. As they do so, the woman reassures her husband that, such are his talents, with more ambition he could have been "top general", rather than merely "general factotum".

Performed by John Carty, Sandra O'Malley and Ciaran McCauley with a physical skill and vocal precision that often characterise Irish actors, and designed with a dusty precision by Jamie Vartan, it is an impressive production of a modern classic. Its modernity receives a twist in the way Britain's recent jubilee celebrations are evoked – satirised, Republicans may say – by the couple throwing confetti to celebrate the arrival of a palpably absent emperor.