 -- The small town of Truro, Massachusetts, is known for its shellfishing, sunsets and quiet beaches.

But that peace was broken on Jan. 6, 2002, when accomplished fashion writer Christa Worthington was found dead in her home overlooking the Atlantic Ocean. Her daughter Ava was 2-and-a-half years old at the time of her murder and found unharmed next to her body.

“She was stabbed through the chest to where the blade nicked the floor,” Maria Flook, author of “Invisible Eden: A Story of Love and Murder on Cape Cod,” told ABC News’ “20/20.” “Her cell phone was left on the kitchen counter with just the digit 9 punched in, as if she might have been trying to dial 911.”

Immediately after her murder, police investigators looked into the relationships Worthington had and put together a timeline of her last days.

And in their investigation, police spoke to a cast of characters -- including her own father and her ex-lovers -- to try to determine who would have had the motive to kill Worthington.

See a list of important persons in the case of Christa Worthington's murder below.

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Christa Worthington

Christa Worthington, 46, was found dead in her Truro, Massachusetts, home on Jan. 6, 2002. Worthington grew up an only child in Hingham, Massachusetts, with her father Christopher “Toppy” Worthington and mother Gloria, and attended Vassar College. In the decades after college, Worthington became an accomplished fashion writer, working for Women’s Wear Daily, The New York Times and Elle magazine, among other international publications.

Tim Arnold

Tim Arnold was a former boyfriend of Worthington and an author who wrote a number of books, including the children’s book titled “The Winter Mittens.” Arnold and Worthington dated for about a year, but he continued to help her take care of Ava after their relationship ended. Arnold discovered Worthington's body at her home and called police. He told police he had gone to her house to return a flashlight he borrowed from her. Arnold had been a suspect in the initial police investigation into Worthington's murder, but police later cleared him of any involvement in her death.

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Thomas Churchwell

Thomas Churchwell briefly dated Worthington in 1998. At the time he was with Worthington, he was a magician known as “The Amazing Tarquin” and performing in New York City. He says, "She had those eyes that would melt you, that probably had melted every man that she was with.” Police questioned Churchwell about his whereabouts during the time they believed Worthington was killed, but later cleared him.

Tony Jackett was the shellfish constable of Provincetown and Truro. It was his job to enforce fishing laws and make sure fishermen had the proper licenses. He is married to Susan Jackett, and the two had six children together. Tony Jackett met Worthington in the summer of 1997, and they began a secret affair. Worthington eventually became pregnant with their daughter, Ava. They initially made a mutual decision to try to keep secret that Tony Jackett was Ava’s father and ended their affair. However, Worthington changed her mind and demanded that Tony Jackett tell his wife. His wife forgave him and welcomed Worthington and Ava into their lives. Police initially suspected Tony Jackett of being involved in Worthington’s murder, but he was eventually cleared as a suspect. After Worthington’s murder, Ava, now 18, was put in the custody of Worthington’s best friend. Tony and Susan Jackett maintained contact with Ava throughout her childhood.

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Christopher "Toppy" Worthington

Worthington's father, Christopher "Toppy" Worthington, was also a person of interest in her murder. Toppy Worthington was a Harvard educated lawyer and a former civil prosecutor for the state attorney general’s office. At the time of his daughter’s murder, Toppy Worthington, then 72, was in a relationship with Elizabeth Porter, then 29, who was a former prostitute and heroin addict. Christa Worthington had apparently been quite upset about the relationship by her father’s relationship with Porter, whom he was supporting financially.

Christopher McCowen

Christopher McCowen is serving three concurrent terms of life in prison after being found guilty of first-degree murder with extreme atrocity, aggravated rape and aggravated armed burglary at Christa Worthington's murder trial. McCowen, who worked as a garbage man for a trash collection company in the Truro area, was one of several men in town who gave a sample of his DNA to police investigating Christa Worthington's murder. He was arrested in April 2005 after police found that his DNA matched DNA found on Worthington's body. At first, McCowen told police he didn’t know Worthington beyond her home being on his trash route, but he later admitted to having sex with Worthington at her house the night police believed she was murder. Police say McCowen told them that another man named Jeremy Frazier was also at Worthington's house that night and that the two of them beat Worthington, but that Frazier had killed her.

At trial, McCowen's then defense attorney said McCowen and Worthington had consensual sex on the Thursday before she was murdered, when he was at her house for a regular trash pick-up -- Worthington's body was discovered on a Sunday. McCowen told "20/20" he lied to police about not knowing her to protect her reputation. Police believe McCowen went to Worthington's house alone the night she was killed.

McCowen has long maintained his innocence.

Jeremy Frazier

Jeremy Frazier, an acquaintance of McCowen's, admitted to being with McCowen at a bar on Friday, Jan. 4, 2002 -- two days before Worthington's body was discovered. Frazier testified as a witness for the prosecution at McCowen's murder trial. He testified that he separated from McCowen later that night and stayed overnight at a friend's house. He denies having any involvement in Worthington's death and denies he went to her house with McCowen on the night in question.

0:17

This article is part of an investigative series by "20/20" and ABC Radio looking into the murder of Christa Worthington and the trial and conviction of Christopher McCowen. The two-hour "20/20" report, "A Killing on the Cape," airs on Friday, Nov. 24 at 9 p.m. ET and the six-part podcast can be heard on Apple Podcasts, Spotify, Google Play Music, TuneIn, Stitcher and under the "Listen" tab on the ABC News app.

Tim Arnold

Tim Arnold was a former boyfriend of Worthington and an author who wrote a number of books, including the children’s book titled “The Winter Mittens.” Arnold and Worthington dated for about a year, but he continued to help her take care of Ava after their relationship ended. Arnold discovered Worthington's body at her home and called police. He told police he had gone to her house to return a flashlight he borrowed from her. Arnold had been a suspect in the initial police investigation into Worthington's murder, but police later cleared him of any involvement in her death.

1:50

Thomas Churchwell

Thomas Churchwell briefly dated Worthington in 1998. At the time he was with Worthington, he was a magician known as “The Amazing Tarquin” and performing in New York City. He says, "She had those eyes that would melt you, that probably had melted every man that she was with.” Police questioned Churchwell about his whereabouts during the time they believed Worthington was killed, but later cleared him.

Tony Jackett was the shellfish constable of Provincetown and Truro. It was his job to enforce fishing laws and make sure fishermen had the proper licenses. He is married to Susan Jackett, and the two had six children together. Tony Jackett met Worthington in the summer of 1997, and they began a secret affair. Worthington eventually became pregnant with their daughter, Ava. They initially made a mutual decision to try to keep secret that Tony Jackett was Ava’s father and ended their affair. However, Worthington changed her mind and demanded that Tony Jackett tell his wife. His wife forgave him and welcomed Worthington and Ava into their lives. Police initially suspected Tony Jackett of being involved in Worthington’s murder, but he was eventually cleared as a suspect. After Worthington’s murder, Ava, now 18, was put in the custody of Worthington’s best friend. Tony and Susan Jackett maintained contact with Ava throughout her childhood.

1:58

Christopher "Toppy" Worthington

Worthington's father, Christopher "Toppy" Worthington, was also a person of interest in her murder. Toppy Worthington was a Harvard educated lawyer and a former civil prosecutor for the state attorney general’s office. At the time of his daughter’s murder, Toppy Worthington, then 72, was in a relationship with Elizabeth Porter, then 29, who was a former prostitute and heroin addict. Christa Worthington had apparently been quite upset about the relationship by her father’s relationship with Porter, whom he was supporting financially.

Christopher McCowen

Christopher McCowen is serving three concurrent terms of life in prison after being found guilty of first-degree murder with extreme atrocity, aggravated rape and aggravated armed burglary at Christa Worthington's murder trial. McCowen, who worked as a garbage man for a trash collection company in the Truro area, was one of several men in town who gave a sample of his DNA to police investigating Christa Worthington's murder. He was arrested in April 2005 after police found that his DNA matched DNA found on Worthington's body. At first, McCowen told police he didn’t know Worthington beyond her home being on his trash route, but he later admitted to having sex with Worthington at her house the night police believed she was murder. Police say McCowen told them that another man named Jeremy Frazier was also at Worthington's house that night and that the two of them beat Worthington, but that Frazier had killed her.

At trial, McCowen's then defense attorney said McCowen and Worthington had consensual sex on the Thursday before she was murdered, when he was at her house for a regular trash pick-up -- Worthington's body was discovered on a Sunday. McCowen told "20/20" he lied to police about not knowing her to protect her reputation. Police believe McCowen went to Worthington's house alone the night she was killed.

McCowen has long maintained his innocence.

Jeremy Frazier

Jeremy Frazier, an acquaintance of McCowen's, admitted to being with McCowen at a bar on Friday, Jan. 4, 2002 -- two days before Worthington's body was discovered. Frazier testified as a witness for the prosecution at McCowen's murder trial. He testified that he separated from McCowen later that night and stayed overnight at a friend's house. He denies having any involvement in Worthington's death and denies he went to her house with McCowen on the night in question.

0:17

This article is part of an investigative series by "20/20" and ABC Radio looking into the murder of Christa Worthington and the trial and conviction of Christopher McCowen. The two-hour "20/20" report, "A Killing on the Cape," airs on Friday, Nov. 24 at 9 p.m. ET and the six-part podcast can be heard on Apple Podcasts, Spotify, Google Play Music, TuneIn, Stitcher and under the "Listen" tab on the ABC News app.

McCowen has long maintained his innocence.

Jeremy Frazier

Jeremy Frazier, an acquaintance of McCowen's, admitted to being with McCowen at a bar on Friday, Jan. 4, 2002 -- two days before Worthington's body was discovered. Frazier testified as a witness for the prosecution at McCowen's murder trial. He testified that he separated from McCowen later that night and stayed overnight at a friend's house. He denies having any involvement in Worthington's death and denies he went to her house with McCowen on the night in question.

0:17

This article is part of an investigative series by "20/20" and ABC Radio looking into the murder of Christa Worthington and the trial and conviction of Christopher McCowen. The two-hour "20/20" report, "A Killing on the Cape," airs on Friday, Nov. 24 at 9 p.m. ET and the six-part podcast can be heard on Apple Podcasts, Spotify, Google Play Music, TuneIn, Stitcher and under the "Listen" tab on the ABC News app.