Dexter Series

The Dexter Series by Jeff Lindsay is a collection of novels featuring the sociopathic vigilante Dexter Morgan. Dexter is a forensic blood spatter analyst who uses his spare time to hunt and kill murderers who have escaped the justice system. He follows his own code of logic called simply "The Code" or occasionally "The Code of Harry" after his adoptive father Harry Morgan who taught him the ethics the code is based on.

The principles of the code are that Dexter can only kill people after finding conclusive proof that they are guilty of murder and that he must dispose of all evidence so he doesn't get caught.

The book series so far features seven novels and has also been turned into a successful TV series of eight seasons so far.