Complex sentence: The series begins in April 1889, six months since the last Jack the Ripper killing, and in Whitechapel H Division is responsible for policing one and a quarter square miles of East London: a district with a population of 67,000 poor and dispossessed.
Split into simpler sentences: The series begins in April 1889, six months since the last Jack the Ripper killing, and in Whitechapel. Whitechapel's H Division is responsible for policing one and a quarter square miles of East London: a district with a population of 67,000 poor and dispossessed.