Obsession is the third episode of the second season. It was released on 7 October 2005.
Singer and superstar Skyler Wyatt reports a knife-wielding intruder in her home. The break-in seems to be connected to the hate mail she has been receiving for the last three months. Don begins to investigate and the body of a paparazzo is discovered in an area overlooking Skyler's home. Don brings in Charlie to analyze the hand-written hate mail and to try to determine where the strange photographs found on the dead body were taken. As the investigation proceeds the brothers are drawn further into the murky world of the paparazzi and celebrity stalking!
Beyond the literal, there is also a sense of celebrity perfumes, like Calvin Klein's Obsession, and similar 'development of the brand'.