Mervyn Peake’s Gormenghast trilogy is packed with original metaphor and simile. In Titus Groan, the first book, I noted two similes for ‘expressionless’, both appropriate, though I think I prefer the second.
See also his description of a blank stare.
‘Her eyes were as expressionless as mushrooms.’
‘… their faces remained as expressionless as powdered slabs.’
Source: Mervyn Peake, Titus Groan,introduction by Anthony Burgess (London: Vintage Books, 1998), p. 321 and p. 282
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