It's hard to say what you might like without knowing a little about you. That said, "Breaking Bad" is the most compelling drama that I have seen in recent years. The main character, Walt, is a high school chemistry teacher newly diagnosed with cancer. In an effort to provide for his family financially in the short time left to him, he first manufactures and then distributes crystal meth. There are consequences.
HBO's "The Wire" is a brilliant examination of the drug trade and those who engage in it on all sides of the law. It's an ensemble cast, understandably dark, and so not quite as much of a "page-turner" as "Breaking Bad."
I also have to give a shout out to the first season of "Veronica Mars," a indomitable teenaged detective confronting the murder of her best friend, the breakup of her family, and being booted from the upper echelon of her school's social pyramid. This sounds like someone trying to pitch an edgier 90210, but Veronica is an entirely different speicies.
I also have found TV series on DVD that can only be watched while on the elliptical to initially be good motivation to trudge down to the basement and eventually a time of the day to which I look forward. Happy ellipting!