Bones

In the early seasons the relationship between Booth and Brennan has to be one of the best leading partnerships in any crime show; it's definitely what got me invested in the show. From there the show's real strengths are developed: the sharp dialogue and fascinating plot-lines are all tied together by the chemistry between the characters.
Unfortunately, as the series goes on the show loses it's way, the season-long cases become less compelling and the show settles into a week-in/week-out plot. Having said that, I am quite impressed at how long the show manages to stay interesting. Most procedural crime series get tedious much faster.
Even still, with the exception of 'Castle', this show is the best crime show still airing.

Still interesting after 10 seasons. There's almost always a case-of-the-week, yet there is also a deeper storyline through the seasons. The dynamic between Booth and Brennan is amazing and I always like to see the different Squints.