There are serial killers and then there are killer who are mad scientists. This up the difficulty and danger level of the killer. Instead of just using a knife they can create a virus that causes you to melt instantaneously leaving no finger prints.
compare Deadly Doctor
and Morally Ambiguous Doctorate
Live Action TV
- Fringe is the most well known examples and almost every episode revolves around this.
- CSI had Dr. Jekyl (who was essentially there to serve as a foil to the newly introduced member of the cast Dr. Ray Langson) who carried out surgery on his victims, generally to kill them (e.g. implanting infected appendices). He turned out to be the son of a restaurant owner who was angry he couldn't study to get his doctorate and began killing off his father's old friends.
it was believed that Jack the Ripper
had medical knowledge (or worked as a butcher) due to the way he cut up his victims. This may or may not have been the case.