A designer is often required to create costumes for animal characters and this presents an interesting problem. How realistic should the costume be? How much information is needed to convince an audience that it is watching an animal rather than an actor? Will a headdress be sufficient and, if so, is it essential to see the actor's facial expressions?
Peter Shaffer's play Equus requires actors to impersonate the horses which obsess the disturbed youth at the centre of the drama. In the introduction to the published text Shaffer specifies that 'any literalism which could suggest the cosy familiarly of a domestic animal - or worse, a pantomime horse - should be avoided'. The animal effect is to be created through mime and movement.

Designer John Napier realised Shaffer's directions by creating stylised horse's heads which were acceptable as both real animals and the horse gods of the boy's imagination. The head is a skeletal structure attached to a padded leather band that runs round the actor's face and chin, and sits above, rather than over, the wearer's head to increase his height. The shape is created from bands of leather and what appears to be silver wire, but is actually a type of cane covered in silver metal foil. This gives it a rigidity and stability while being light for the wearer. Further height is added by the hooves constructed from metal rods. The actor, who wears a tracksuit of chestnut-coloured velvet, is clearly visible and, said Shaffer, must 'stand upright, as if the body of the horse extended invisibly behind'. The overall effect, created by a simple costume and its wearer's movements, was, in the words of the theatre critic of Punch magazine, 'gravely spectacular and unearthly'.