The Customer. In Season 3, a glimpse is given into the life of drug trade's consumer base in hilarious and disturbing fashion. As the sunny and bouncy pop song "Windy" by The Association plays over a montage of Wendy the meth-addicted prostitute plying her "trade" in the front seats of a long succession of clients' cars and enjoying the fruits of that labor. The juxtaposition of the aggressively happy song with the tragically sad scenes would be funny for the irony if it weren't probably so sadly accurate.
The Reveal. Season 4 focuses extensively on the war between Walter White and Gustavo Fring. In the penultimate episode, the son of Jesse's girlfriend falls ill to an apparent poisoning. Pinkman blames Walter, as a cigarette he has been carrying all season containing a lethal vial of ricin has gone missing. After White emerges victorious over Fring in unforgettable fashion, the new lord of the meth trade sits on his patio repeatedly spinning a gun on a table. The gun twice stops pointed directly at the grim-faced Walt, giving the impression that he may be harboring suicidal thoughts. The third time, it points toward a potted plant on the rock garden. After showing how White earlier sums up the day to his wife Skyler ("I won"), the camera slowly pans in to the gentle chimes and soft guitar opener of "Black" by Danger Mouse and Daniel Luppi. The audience is shown the tag of the plant, reading Lilly of the Valley, revealing that Walter White had, in fact, poisoned the young son of Jesse's girlfriend as part of his plan to take down Fring. Black, indeed.
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See also: Breaking Bad's Vince Gilligan Reveals the Exact Moment Walter White "Broke Bad" Forever
