ALMOST four years to the day before Marilyn Rynn disappeared, another Dublin woman left her home in Tallaght to do some last minute Christmas shopping and never returned.
Patricia Doherty, a prison officer and mother of two young children, walked out of her family's life on December 23rd, 1991.
Only by chance did Ms Doherty's fate emerge. The following June, dry weather caused the peat bank where she had been buried to subside and her body was found by ramblers at Killakee, in the Dublin Mountains. She had been murdered and buried there.
Josephine Dollard (20), from Kilkenny, disappeared while hitch hiking home from Dublin on November 9th and has not been seen since. Gardai believe she, too, has been murdered and her body hidden somewhere.
Gardai who have investigated such disappearances recite cases with striking similarities but which are almost certainly not connected.
Murders of young women tend to happen in the darkness of winter nights, often around the Christmas holidays when women are travelling unaccompanied through the countryside.
Marilyn Rynn's murder immediately brought to one officer's mind the murder of Phyllis Murphy (23), who disappeared after leaving a dance in Newbridge, Co Kildare, on December 22nd, 1979, exactly 16 years before Ms Rynn was killed.
Ms Murphy is also believed to have been pursued, raped and murdered. Her body was also not found until 26 days later, in a thicket off a back road in the Wicklow Gap.
Another December murder victim was Marie Kilmartin, who disappeared nine days before Christmas 1993. Her body was found by a garda cutting turf in a bog outside Portlaoise the following June. Her murder has not been solved. Ms Rynn's murder, on the facts known so far, also bears some resemblance to that of Patricia O'Toole, the 31 year old woman abducted and murdered in August 1991.
Ms O'Toole was the victim of a chance encounter with a man from whom she sought directions near the South Circular Road, Dublin. She, too, had just enjoyed a night out with friends and had been drinking alcohol.
Her misfortune lay in allowing her murderer, Sean Courtney into her car. Courtney, who insisted that his mind was unbalanced at the time, misdirected her and eventually attempted a violent sexual assault which resulted in her death.
In 1991, the year Patricia O'Toole was killed, nine other women were murdered, although only Patricia's death captured the public imagination. Her murderer was caught after two bar men, going home from work, correctly placed Ms O'Toole at a location away from the centre of the main Garda investigation and speaking to the man who killed her.
All the 1991 murders, save that of Patricia Doherty, were solved. In all but two cases, the murderer was known to the victim. Three were married to their killers in one case for almost 70 years and one woman was killed by a deranged son.
The official clear up rate for murder in the Republic is probably one of the highest in the world. However, some high profile cases remain unresolved.
Grace Livingstone was attacked and shot dead in her home at Malahide, Co Dublin, in December 1992.
Antoinette Smith, a 27 year old mother of two from Clondalkin, was also murdered and buried in the Dublin mountains in July, 1987. Her body was found in Killakee Woods the following April.
Gardai have never recovered the body of Annie McCarrick, the American student who disappeared and is believed to have been murdered in March 1993.
No one has been charged with the murder of Philomena Gillane, from Caltra, Co Galway, who was shot and stabbed to death. She was seven months pregnant. Her body was found in the boot of a car two weeks after she disappeared.
The body of Eva Brennan, who disappeared from Terenure, Dublin, in July 1993 has never been found. No one has been convicted of the murder of Deirdre Mulcahy, a 19 year old woman from Midleton, Co Cork, who was raped and strangled in September 1989.