See, when a serial killer terrorizes an area and then disappears, people worry. Where did the killer go? Why did he leave? Why did he start? Is he coming back? There are just so many terrible thoughts that can run through a person's mind. Then, when bad things happen in the area, well, the thoughts multiply. Is the killer back? Why are these things happening? The police in this drama are tasked with trying to keep Whitehcapel calm after the disappearance of Jack the Ripper. The series is based (at least loosely) on real people and events (like Jack the Ripper and his grisly murders).