- a baleful look.
- a black lie.
- a dark purpose.
- a sinister smile.
- bar sinister.
- black deeds.
- dark undercurrents of ethnic hostility.
- Darth Vader of the dark side.
- forbidding thunderclouds.
- his black heart has concocted yet another black deed.
- his threatening behavior.
- his tone became menacing.
- ominous rumblings of discontent.
- sinister storm clouds.
- the scheme of some sinister intelligence bent on punishing him.
- the situation became ugly.
- ugly black clouds.