It started as a missing person appeal to find two missing pensioners from Weybread in May 2016.
Within days, it became a double-murder investigation into the deaths of Peter Stuart and his wife, Sylvia.
The body of Mr Stuart, 75, was found by police in woodland close to his home in Mill Lane. He had died from multiple stab wounds.
But Mrs Stuart’s body has never been found – and now, a year on, Suffolk Police has renewed its appeal for information.
The 69-year-old was last seen in Goodies Farm Shop in Wood Lane, Pulham Market on Sunday, May 29, at 10.18am.
Ali Qazimaj, 43, from Tilbury in south Essex, was jailed for at least 35 years for their murder in March.
Although our active searching has stopped, as I said after the conviction of Qazimaj I have promised the family that I will continue to follow up any information that assists in locating Sylvia and this remains the caseSenior Investigating Officer DCI Andy Guy
Although active searching has stopped, a spokesperson for Suffolk Police said new searches would be conducted if new information was received.
Senior Investigating Officer DCI Andy Guy said: “Despite a huge number of officers from three counties completing hundreds of hours of searches Sylvia remains missing. Searches were conducted around the Stuart’s home address, the entire route between Weybread and Tilbury and the home and workplace of Ali Qazimaj.
“Although our active searching has stopped, as I said after the conviction of Qazimaj I have promised the family that I will continue to follow up any information that assists in locating Sylvia and this remains the case. I would also ask anyone who may have information to call us.”
Qazimaj, arrested in Luxembourg in June 2016, was described as a “ruthless and accomplished killer” by Mr Justice Stuart-Smith when he was sentenced earlier this year.
It took a jury less than four hours to find Qazimaj - who insisted that he was a man called Vital Dapi who had never before been in the UK - guilty of the murders of Mr and Mrs Stuart.
The couple had been reported as missing from their home in Mill Lane, Weybread in May last year after they failed to turn up for a weekly line dancing class and had not been seen for some time by neighbour.
A police search revealed the body of Mr Stuart partially submerged in a stream in a wooded area at the rear of the couple’s home. He had been stabbed nine times with what the jury heard had been “considerable force”.
Despite following up hundreds of lines of enquiry, police have been unable to locate Mrs Stuart, 69, but prosecutor Karim Khalil QC told the trial there was “compelling evidence” that she too had been murdered by Qazimaj.
Among more than 30 witnesses who gave evidence was a fingerprint expert who said there was “no doubt” that prints found on an abandoned car in Dover belonged to Qazimaj while a DNA specialist said traces of blood and hair found in the same vehicle came from Mr and Mrs Stuart.
Anyone with information should contact police on 101.