A taxi driver brutally murdered almost 40 years ago, a banker shot on his doorstep in Scotland, and a woman killed in her own home in Darlington are among the shocking cases which have never been solved.
The victims range in age from missing 14-year-old Sarah Benford who is believed to have been murdered, to 69-year-old Nora Tait.
Among the unsolved murders are that of Alistair Wilson who was shot dead on his doorstep in Nairn in 2004
Meanwhile, the killer of George Murdoch still remains at large. The taxi driver was attacked with a cheese wire while working in Aberdeen on 29 September, 1983.
Police have continued to hunt for those responsible for the murders in order to get justice for the victims and their loved ones.
Here are some of the most shocking unsolved murder cases from the past four decades.
Among the unsolved murders are that of Alistair Wilson who was shot dead on his doorstep in Nairn in 2004