Editor's note: The following story on "House of Cards" contains spoilers. If you'd rather not know anything about Season 1 or Season 2, click on this story.  (CNN) -- When we last saw South Carolina Congressman Francis Underwood on Netflix's "House of Cards," he was being offered an appointment to the vice presidency of the United States.  How much trouble can that cause?  Given what Underwood did in the first season of the show, probably more than anybody anticipates. Don't expect him to be the glad-handing, funeral-attending type of VP; Underwood is more likely to be holding a knife or two, the better to stab people in the back -- or, if it's necessary, in the front.  "House of Cards," which helped establish Netflix as an original programmer -- rather than those folks who send you DVDs in red envelopes -- returns Friday for its second season. Like the first, it will be available for download all at once, which may mean that a lot of Valentine's Day dinners grow cold while fans binge on watching 13 straight episodes.  As the second season begins, Kevin Spacey's Underwood reveals that the vice presidency won't change his cold, pragmatic cardiac muscle.  "One heartbeat away from the presidency and not a single vote cast in my name," he says at his swearing-in. "Democracy is so overrated."  'He believes ideology is a form of weakness'  It's a long way from the beginning of the first season, when Underwood was denied his desired job as secretary of state. But in a long-running game of "don't get mad, get even," Underwood -- with help from Doug Stamper, his subtly brutal chief of staff (Michael Kelly); Claire, his devoted and equally conniving lobbyist wife (Robin Wright); and Zoe Barnes, a pliable, ambitious reporter (Kate Mara) -- managed to knock down his obstacles and maneuver his way up the Washington food chain.  If a few bodies were left in his wake -- figuratively and, in one case, literally -- well, the ends justify the means. As Underwood noted in the very first episode as he put a wounded dog out of its misery, "I have no patience for useless things."  But that's not to say that Underwood doesn't also want to make the system work. In an interview last fall with CNN, showrunner Beau Willimon explained that Underwood, at heart, is "an optimist," though he understands the darker view.  'House of Cards' creator Willimon plays a solid hand  "Where I think people mistake his optimism for cynicism is that he's unapologetically self-interested. He believes ideology is a form of weakness -- a form of cowardice," Willimon said. The writer and producer observes that one of the character's models is Lyndon Johnson, known for his shrewd knowledge of the legislative process both as a senator and as president.  Willimon added that "House of Cards" isn't necessarily a show about politics, despite its Washington setting. It's a show about power -- in all its manifestations.  "That power is displayed in our love lives, or our work environments, the way we comport ourselves when randomness brushes up against us," he says. And, he adds, power can be more useful than money: "Power has no limits if you're willing to go far enough in order to get as much of it as you can."  'Mr. Macbeth Goes to Washington'?  Naturally, Willimon and his stars have been tight-lipped about how far Underwood will take things in a show The Kansas City Star nicknamed "Mr. Macbeth Goes to Washington." Trailers and tidbits, however, offer some tantalizing hints.  There's a suggestion that Underwood could be implicated in a murder investigation. Perhaps Barnes might be locating her ethics. A New York Times Magazine profile of Willimon mentioned a "super-duper-double-major spoiler."  And Underwood appears headed for a showdown with wealthy industrialist -- and fellow power broker -- Raymond Tusk (Gerald McRaney), a friend of the president.  Just as intriguing is the future of Underwood's wife, Claire. In the first season's early episodes, she seemed more troubled by unethical behavior than her husband; after all, she was a lobbyist for environmental issues. But that changed as she found her own livelihood threatened.  In this, she is much like her husband, said Wright.  "She is a pragmatist in the art of war," the actress told The New York Times.  However the second season concludes, "House of Cards" has already been a winner. Netflix spent $100 million to produce the show's first two seasons. In return, the show was nominated for eight Emmy awards last fall, winning three, and Netflix's subscriber base and stock price have both hit new highs. The service has quickly become a major player for original programming, with last summer's "Orange Is the New Black" also earning raves.  The company recently renewed "House of Cards" for a third season.  In the meantime, one can only wonder whether a better Shakespearean parallel for Underwood is "Othello's" Iago, dropping poisoned hints in the president's ear. All Willimon will promise is the show will hold on to its darkness.  "There are people who don't like the level of darkness, who find the characters unsympathetic," he told the Times Magazine. "And we need to own that."
"House of Cards" returns for season 2 on Friday. Kevin Spacey's character is now VP and still wielding power cleverly.