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A group of investigators have re-examined some of Ireland’s most well-known cold cases as part of an upcoming documentary.

Mary Aiken, a research psychologist originally from Co. Cork, has some interesting theories about some of Ireland’s unsolved cases as part of TV3’s new series “Crime in Mind.”

Speaking about the case of Annie McCarrick, the Irish-American who went missing in 1993, Aiken said that the Long Islander had a secret date on the last night she was seen.

"It has long been believed that on the last day she was seen alive Annie went to Enniskerry for a walk… however, based on the behavioral evidence, the ‘Crime in Mind’ investigative team have come up with some fresh insights indicating that Annie went to Enniskerry for an entirely different purpose…it is likely that Annie had a secret date," Aiken states during the new documentary.

The new series consists of six hour-long episodes that delve into separate high profile cold cases, including the disappearance of McCarrick, Phillip Cairns and JoJo Dullard.

Regarding the murder of Raonaid Murray, a school girl from Dun Laoghaire who was stabbed to death over a decade ago Aiken said: "Lots of theories have been proposed as to who killed Raonaid. We examined the evidence and . . . it is likely that this was an accidental death, a case of intimidation that went too far by somebody known to Raonaid."

Reflecting on the case of Phillip Cairns, a 13-year-old school boy who went missing in 1986 after leaving his home to return to school after lunch, she says: "Most people believe that Philip Cairns was abducted while walking to school. We believe Philip did not intend to go back to school that day."

Aiken is joined by forensic psychologist Dr. Mike Berry and Martin Donnellan, an assistant commissioner with the Irish police force, as part of the team that is reviewing the cases.

"In all of the programs the team generated fresh behavioral insights into these cold cases. Most have had no new leads for many years," Aiken says.

Watch Annie McCarrick episode here.

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Missing New Yorker Annie McCarrick