1.   His face had darkened with shame at having his pleasure aroused in public by one of his daughters.

2.   She handed him the letter and his face darkened.

3.   Her face darkens to a deep red when she gets angry.

4.   There was an icy contempt in her voice, and his face darkened in anger before he gave a faint dismissive shrug of his broad shoulders.

5.   His lean face darkened and he muttered something in Portuguese beneath his breath.

6.   But then her face suddenly darkened.

7.   His face quickly darkened.