The unsolved murder of a 78-year-old woman in a Surrey village 40 years ago is to be reviewed by police.
Kathleen Maud Cock was found dead in the kitchen of her home in Surrey Gardens, Effingham, on 27 November 1975 - she had been beaten around the head.
Entry to her house had not been forced, and the only items stolen were her wedding and engagement rings.
Blood believed to be that of Mrs Cock's attacker, found by her body, will now be subjected to new forensic tests.
Cold case detectives hope that advancements in forensics could ultimately lead to finding her killer.
Widow Mrs Cock was last seen shopping for Christmas presents in Guildford the day before her body was found by a neighbour.
Phil Waters, the village bobby at the time, said she "kept herself very much to herself, lived in her little cottage, and didn't come out to talk to the village policeman".
She was known as kind-hearted and intelligent, and was nicknamed "The Angel".
The murder weapon - believed to have been a hammer - was never found despite searches of local ponds and nearby land.
Two suspects were identified - one was a man in a local cafe asking for directions to Surrey Gardens, who was found and eliminated from the inquiry. A second man seen lurking in people's gardens in the nearby area was never found.
Det Supt Ronald Underwood, who headed the investigation, said he did not believe the case should ever be laid to rest.
"All the time there is the possibility of catching somebody who has committed a crime as horrible as this... what's to say that they aren't going to kill somebody else again?"
Surrey Police said the case was reviewed in 2002 and 2006, but no new leads emerged.
A spokeswoman said the new forensic review would "take a number of months".