Butter Wouldn't Melt takes the form of a tightly composed bust portrait, focusing in on a sharply dressed fox whose sidelong glance carries every ounce of mischief the title implies. Walker's choice of phrase is a brilliant one. To say that butter wouldn't melt in someone's mouth has long been a favourite piece of British understatement, the kind of remark made with a raised eyebrow about a character whose innocent appearance is not entirely to be trusted. Pairing the expression with a fox, that most legendary trickster of the British countryside, gives the painting its gentle comic charge.

Dressed in the manner of a thoroughly respectable city gentleman, the fox wears a deep navy blue jacket, a crisp white shirt with a softly ruffled collar and an eye-catching mustard yellow tie tied with the air of someone who knows precisely the impression he is making. His russet fur is rendered with rich tonal warmth, the deep auburns and burnt oranges of his face contrasted beautifully against the cool greys and inky blues of the background and suit. The eyes are the painting's masterstroke, alert, intelligent and just faintly amused, fixing the viewer with the unmistakable expression of someone who has heard the accusation many times before and has absolutely no intention of confirming it.

Jonathan Walker's loose, expressive watercolour technique is shown here at its most refined, with the pigment allowed to pool and bleed across the paper to give the fur, fabric and shadowed background a wonderfully tactile quality. Areas of the paper are left exposed around the edges of the figure, lending the portrait an immediate, almost sketch-like quality that draws the eye straight to the fox's face. As one of the most recognisable names in contemporary British wildlife art, Walker has built a devoted following of collectors drawn to his rare ability to find the deeply human within the animal world. His paintings imagine a parallel rural society where foxes, badgers, hares and mice adopt human habits and personalities without ever losing their essential wildness, a tradition rooted in the great heritage of British illustration yet entirely contemporary in spirit.