Watch an old movie, one of the musicals, when the air in your house is too still and hot to allow you to move or think or do anything other than draw breath and let the world pass through you like water through a sponge. Let the commercials break against your listlessness like waves against a cliff-face, slowly eroding you until you crumble into alertness and irritation, to be settled by the black and white flicker of the dancing.

Watch how the songs intrude on the story, and how the work with it. Notice the clockwork perfection of the B plot, Edward Everett Horton bumbling around in a panic, Margaret Dumont opening her mouth wide in mock horror toward an end mathematically predictable, standard moral lesson putting paid to the opium dream of the straight man.

Notice the faces on the leads as they dance for the first time, the solemn joy on the man’s face, the hopelessness that succeeds the first faint tremors of pleasure on the woman’s. How sad she looks, how trapped, as her shoulders sway backwards from his, perfectly spaced, perfectly timed; in this despair you can read the second relationship, the doomed marriage, the lifelong engagement — but then, too, the faint ripples of resolution, the breakers that will roll on and on until they break on the shore, and sweep the sand clean.