John Cassavetes exuded such a potent kind of mercurial quality.  It seems so wound up in him, so focused.  I always found his specific embodiment of this quality of energy bewitching to watch, and observe. In the screencap above Cassavetes' character is lowering his car from the hydraulic lift (in a mechanic's garage), and that's one moment of his reaction as he's waiting the several seconds it takes to get his car down.  As his car is lowered, his impatience rises.