Possible Clues:

• Gray in a picture?
• "The Picture of __ Gray"
• Gray painted by Basil Hallward
• Greek academic with stifled expression looking back
• Gray in a novel painting
• Literary portrait by Mondrian, roughly trimmed
• Wilde's 'The Picture of __ Gray'
• Wilde's "The Picture of __ Gray"
• Oscar Wilde's 'The Picture of ___ Gray'
• Gray in an Oscar Wilde story