The fourth season of Breaking Bad begins mere moments after last season's finale, which, though not as melodramatic as the "Who Shot J.R.?" episode of Dallas, was quite a cliffhanger, with Walt (Bryan Cranston) and Jesse (Aaron Paul) held at gunpoint in their hellish red-walled meth lab, waiting for what seems like hours to learn the consequences of their ruthless murder of the naïve and largely innocent Gale (David Costabile). When fried-chicken franchise owner/drug lord Gus (Giancarlo Esposito) finally arrives, it's both shocking and inevitable. "Go back to work," are his only words following a brutally efficient demonstration—involving a sharp box cutter and a bare throat—of his seriousness. Apparently, going back to work also means cleaning up the gory mess on the floor. Violence on Breaking Bad is normally quick and stylish, but this scene is notable for its severity and length, effectively demonstrating Gus's coiled ruthlessness.
This single moment hangs over season four like the sword of Damocles. Walt has no doubt that once he and Jesse are of no use to Gus, they'll face the same end. He also knows that it's all really just business; after all, Walt and Jesse did the same to Gale. Though the pair had killed before, it was never in such a calculated and cold-blooded way, and it never involved someone who wasn't directly threatening their lives.
Given enough time, paper, and math, Walt can justify any action. He even insists he's not "a drug dealer," but rather a "manufacturer." This is just one of the many ways he differs from Jesse, who's always been too empathetic to make a successful criminal. Instead of justifying his actions, he often just blames himself—something Walt avoids at all costs. So it's no surprise that while Walt has come to terms with Gale's murder as collateral damage, the crime weighs heavily on Jesse's conscience. Drifting through his days and nights, back taking meth, and allowing his home to be turned into a 24-hour public party zone, he seems horrified to be left alone with his thoughts. He reaches out to Walt like he often does, only to be rebuffed as usual.
Walt's thoughts are now almost entirely devoted to self-preservation, and in the second episode of the season, "Thirty-eight Snub," he comes to the realization that it may be the very point of his business. He purchases a gun with its serial number filed down and goes around town packing—less like a manufacturer and more like a bona fide drug dealer now. Gale's murder has deeply marked both Walt and Jesse, but instead of communicating with each other, they move back into their own private corners, becoming lost in their own paranoid thoughts.
Creator Vince Gilligan focuses on his main characters here, but without sacrificing his fine supporting cast. In fact, the subplots involving Skyler's (Anna Gunn) deeper involvement in Walt's business and Marie (Betsy Brandt) and Hank's (Dean Norris) struggles with his physical condition after being shot last season are some of the stronger B plots the show has presented to date. What Gilligan truly excels at, however, is pacing: The series never feels like it's marking time. Breaking Bad is a complete work, one thought out long in advance and unfolding in its own time. This is one of the rarest finds on television: a show where cast and character are so perfectly matched by a creator who understands exactly what journey he wants take his audience on.