One time a man approached me with a maniacal grin, opening his raincoat to reveal a machete.
You've been quoted as saying you were a "thug" when you were younger and that your behavior was "maniacal."
The episode “Crawl Space,” in which Walter discovers the money is gone and breaks into maniacal laughter, was a critical favorite.
Dick Cheney was maniacal in his debate preparation, and it showed.
Protest all you want about giving someone else a chance, but that maniacal laugh alone deserves its own little trophy.
A maniacal patient wore on her head a tent of newspaper to keep the devil from coming through the ceiling and attacking her.
The laugh was repeated, and the sound was even more wild and maniacal.
But his servants knew when anything weighed upon his spirits, by his fierce, short, maniacal temper.
If it was fast and furious before, it is maniacal madness now.
The dwarf, now aroused to maniacal fury by the persistance in my refusal, slowly approached me to carry his threat into execution.
maniacal ma·ni·a·cal (mə-nī'ə-kəl) or ma·ni·ac (mā'nē-āk')
Suggestive of or afflicted with insanity.