The idea of a serial killer who only kills other serial killers sounds like it could be a really clichéd B-movie. Instead, the television series Dexter, based on the Dexter novels of Jeff Lindsay (pen name of Jeffry P. Freundlich), is a fascinating and perfectly judged character study as well as an entertaining programme.

Dexter (Michael C Hall) is a blood splatter analyst for the Miami police department who also is a serial killer. However, he only kills people who have killed (and more than once) and haven’t been captured, keeping only a blood sample as a memento. He was taught how to put on a normal façade and exist in normal society by his adoptive father, Harry, who was a celebrated policeman, who recognised what Dexter was but showed him how to channel the impulse against those who deserved it. We see these flashbacks to his youth with his father throughout the show, to give us the development of Dexter.

We meet Dexter as he kills a family man who had killed boys in his youth, before we see him working at the police station, and watch as he becomes involved with what will become known as The Ice Truck Killer, where he helps his adoptive sister, who also works for the police, to get on the case. We also see Dexter in his relationship with a woman (as part of his façade of normality, he must have a girlfriend) who is as damaged in her own way as he is – there is no sex, something that Dexter has no interest in.

There are two aspects of the show that make it wonderful viewing. Firstly is the performance by Hall as Dexter – it is mesmerizing and captivating, showing all his flaws and strengths and conflicts. The look he gives straight to the camera at the end of the first episode, where he finds the clue left for him by the Ice Truck Killer, is exquisite – it should throw you out of viewing experience, but it makes you smile and want to watch more. The second aspect is the precision of the balancing act; this could be just awful, but the strength of the setting, the characterisation of the rest of the cast, the decision to show Dexter’s crimes (I’m watching the series on ITV – quite a bold decision for the bland mainstream of their usual output – so there might be watering down of the more gruesome details) as well as his contributions to society all make for a remarkable show.