Complex sentence: An upper-middle-class couple, Dick and Jane Harper, in which the husband loses his job; they fall through the cracks of society in the United States and then become high-class thieves to get back all they lost.
Split into simpler sentences: An upper-middle-class couple, Dick and Jane Harper, hits a hump in their living the good life when the husband loses his job. Falling through the cracks of society in the United States, they then become high-class thieves to get back all they lost.