Courtesy of LeonardoDaVinci.net

This sombre portrait from around 1495 or later of Christ's apostle Judas shows a man with good intentions who, for egotistical reasons, decided to betray his friend and master. The look on the face is uneasy. The strain in the expression shows disbelief and a grim determination to carry out a disloyal act as if it were justifiable.

Leonardo's drawings of the apostles around the table in the great mural The Last Supper at Santa Maria Delle Grazie are among the most powerfully emotive faces ever used for this theme. Many lesser artists of the period could not achieve Leonardo's quality of realism and often descended into caricature. But here there is no doubt about the dark thoughts in this man's head. They show, subtly, on his upturned face.