Prepare to be haunted. Peter Shaffers 1973 drama centres around an appalling act of violence. Teenager Alan Strang is accused of blinding a stable full of horses. Why has he committed such a seemingly senseless act? What will his psychiatrist make of this outrage? This is a play full of questions, often peppered with puzzling, non-naturalistic language. It has a poetic sweep drawing on a rich seam of mythic, religious and therapeutic reference. Though it is not an easy watch, nor an evening of easily palatable entertainment, it is a powerful piece of pure theatre galloping with emotional energy and raw emotion. It is also incredibly physical almost a choreographed in its intensity. Alan, the only son of repressive parents (mother a religious prude, father a frustrated dullard), is a loner who finds it hard to make friends except with horses. He is fixated on his equine world and even has a picture of a staring horse (watch out for eye references) above his bed. For the troubled boy-man, horses wield a god-like power, creatures to worship, an omnipotent deity to be loved. The play is (unreliably) narrated by the character of Dr Dysart a bespectacled shrink working in a drab hospital. Drab in seventies clothing, beige suite and crumpled shirt, he is a physician who desperately needs healing himself. Dysart is suffering the mother of mid-life crises; can patient Alan and his horse-obsession offer something of value for the troubled therapist? The revival of the play by English Touring Theatre and Stratford East refreshes Shaffers great work (thought by many to be a masterpiece) with some amazing theatrical hocus pocus and intense physicality not least the outstanding portrayal of the muscular and elastic movements of horses performed by the equally muscular Ira Mandela Siobhan and Keith Gilmore. Ethan Kai is equally impressive as the brittle, nightmare-haunted Alan. Dysart, the central character around which the whole play revolves, is superbly performed by Zubin Varla who brings a thin-skinned vulnerability to the part. The exciting lighting design and creepy mood music underscoring much of the evening added to the unsettled atmosphere of this deeply mysterious play. Even though some of the allusions in Equus are hard to grasp, one can thoroughly enjoy the top-notch theatrics and first-rate performances on show. It is certainly worth a canter to the Arts Theatre but beware, its power will haunt you all the way home and beyond.