And, removing his boots, he followed the Queen into the Palace, as she led the way with a baleful expression upon her dark and inscrutable face.
F. Anstey. The Black Poodle and Other Tales (1896)
---
And then the flash of intelligence was gone, and O’Brien’s face was as inscrutable as everybody else’s.
George Orwell. 1984 (1949)
---
They feel hard, unwinking, like the shells of beetles: black, polished, inscrutable.
Margaret Atwood. The Handmaid's Tale (1986)
---
The colonel was still in grave peril. Intuition warned him that he was drawing close to some immense and inscrutable cosmic climax, [...].
Joseph Heller. Catch-22 (1961) p. 210
---
this stillness of life did not in the least resemble a peace. It was the stillness of an implacable force brooding over an inscrutable intention. It looked at you with a vengeful aspect. I got used to it afterwards;