Mary Ann "Polly" Nichols (née Walker; 26 August 1845 – 31 August 1888) was one of the Whitechapel murder victims.
 Her death has been attributed to the notorious unidentified serial killer Jack the Ripper, who is believed to have killed and mutilated at least five women in the Whitechapel area of London from late August to early November 1888.
The Texarkana Moonlight Murders, a term coined by the news media, references the unsolved murders committed in and around Texarkana in the spring of 1946 by an unidentified serial killer known as the "Phantom Killer", or "Phantom Slayer".
 The killer is credited with attacking eight people within ten weeks, five of whom were killed.
 The attacks happened on weekends between February 22, 1946 and May 3, 1946.
 The first two victims, Jimmy Hollis and Mary Larey, survived.
 Some police officers are not sure if their attack was connected with the murders.
 The first double murder, which involved Richard Griffin and Polly Ann Moore, happened four weeks later.
 The second double-homicide, involving Paul Martin and Betty Jo Booker, occurred exactly three weeks from the first murders.
 The Texas Rangers came in to investigate, including the famous M. T. "Lone Wolf" Gonzaullas.
 Finally, almost exactly three weeks later, Virgil Starks was killed and his wife, Katie, was severely wounded.
 Most officials no longer connect that attack to the other murders.
 Contrary to popular belief, the killer did not attack during a full moon, but did strike late at night.
Annie Chapman (born Eliza Ann Smith, c. 1841 – 8 September 1888), was a victim of the notorious unidentified serial killer Jack the Ripper, who killed and mutilated several women in the Whitechapel area of London from late August to early November 1888.
Whitechapel is a British television drama series produced by Carnival Films, in which detectives in London's Whitechapel district dealt with murders which replicated historical crimes.
 The first series was first broadcast in the UK on 2 February 2009 and depicted the search for a modern copycat killer replicating the murders of Jack the Ripper.
Elizabeth "Long Liz" Stride (née Gustafsdotter) (27 November 1843 – 30 September 1888) is believed to be a victim of the notorious unidentified serial killer called Jack the Ripper, who killed and mutilated several women in the Whitechapel area of London from late August to early November 1888.
The Edgecombe County serial killer, also known as the Seven Bridges Killer, is an as yet unidentified serial killer in the surroundings of Edgecombe and Halifax counties in North Carolina, United States.
 There are ten suspected victims, all African-American women, and the remains of eight have been recovered.
 It is suspected that Antwan Maurice, a registered sex offender who was charged with a murder fitting a similar profile, was responsible for the Edgecombe deaths.
 All of the victims had a history of drugs and/or prostitution.
Jack the Ripper is the best-known name for an unidentified serial killer generally believed to have been active in the largely impoverished areas in and around the Whitechapel district of London in 1888.
 The name "Jack the Ripper" originated in a letter written by someone claiming to be the murderer that was disseminated in the media.
 The letter is widely believed to have been a hoax and may have been written by journalists in an attempt to heighten interest in the story and increase their newspapers' circulation.
 In both the criminal case files and contemporary journalistic accounts, the killer was called "the Whitechapel Murderer" and "Leather Apron".
The Oakland County Child Killer (OCCK) is an unidentified serial killer responsible for the murders of four or more children, two girls and two boys, in Oakland County, Michigan, United States in 1976 and 1977.
 Several theories and suspects have been named in the case, but despite all these theories, the cases remain unsolved and the killer(s) have never been identified.
The Whitechapel murders were committed in or near the impoverished Whitechapel district in the East End of London between 3 April 1888 and 13 February 1891.
 At various points some or all of these eleven unsolved murders of women have been ascribed to the notorious unidentified serial killer known as Jack the Ripper.
Mary Jane Kelly (c. 1863 – 9 November 1888), also known as Marie Jeanette Kelly, Fair Emma, Ginger, and Black Mary, is widely believed to be the final victim of the notorious unidentified serial killer Jack the Ripper, who killed and mutilated several women in the Whitechapel area of London from late August to early November 1888.
 She was about 25 years old, and living in poverty at the time of her death.

Question: Whitechapel is a series that depicted a killer who was copying the actions of which unidentified serial killer?
Answer: Jack the Ripper