But she couldn't wait without imposing an unnatural calm which would make killing him impossible.

Here, in the semi-darkness, there was an unnatural calm, as he sat with the dead.

The peace held like an unnatural calm for a long time.

But a cool, almost unnatural calm had hit her once she was back in the bustle of the city.

But still there was no wind, just a deadly unnatural calm.

She straightened, and her face assumed an expression of almost unnatural calm.

"Only this," she replied in a voice of unnatural calm.

So," he said after a moment, with a sort of unnatural calm, "we've got to get the thing licked fast.

The unnatural calm was beginning to slip away from me on tiny cat paws of anxiety.

The gentle breezes of the afternoon had given way to an unnatural calm.