This series is one of the many wonderful British TV series which we do not get in the US. Like most British series, the episodes are longer than in any US series, which allows more character development and more twists. It also has a more finely nuanced set of conclusions than the typical US series. Perhaps, more jaded than Americans, the ending of each episode is less likely to be "happy ever after", with both villain and hero getting their just desserts. The acting is always excellent, and so is the writing.