Complex sentence: Nearly two years have passed since the end of the previous episode; two FBI agents drive in a car, the agent driving states "Nobody ever went broke underestimating the taste of the American public," a quotation of a line by H.L. Mencken.
Split into simpler sentences: Nearly two years have passed since the end of the previous episode. Two FBI agents drive in a car, and the agent driving states: "Nobody ever went broke underestimating the taste of the American public", paraphrasing a line by H.L. Mencken.