Series 1, Episode 3
The episode concentrates on Kate's back story through a series of flashbacks (which actually help the plot along smoothly without it being a distraction) and how she came to be the criminal in the story. The doctor is faced with a dilemma when it is revealed his patient, the marshall, is inevitably going to die, and the strange Locke helps to find the missing dog for Walt.
Exciting developments are really bringing a strength to the series so early in. There are some good character definitions and
enough drama to keep you glued to your seat. I think a lot of the success is in the editing of the scenes, coupled with a very interesting script.