The execution-style killing of Lois Tolley will feature on tomorrow's episode of Police Ten 7.
The 30-year-old was stabbed and shot at point-blank range in her Ward St, Upper Hutt, home in December last year.
There is still a dedicated, professional team working hard on the case and determined to find those responsible, police said.
More than 100 people had been spoken to by police and statements obtained.
Hours of CCTV footage is still being worked through with positive results by the Operation Archer team.
Some of this CCTV footage shows four men arriving and leaving Tolley's Ward St address, and vehicles of interest to the police team.
Detective Senior Sergeant Glenn Barnett said in February police were looking for the owner of a silver vehicle seen in the area at the time of the murder
"The team are making good progress and working hard to get the right result for the family," Barnett said.
"Someone out there knows information that is vital to the inquiry. Now is the chance to come forward."
"We'd encourage people to watch the Police Ten 7 show and to get in touch with the information you're holding, however small you may think it is.
"Your calls will be treated in confidence and acted on by the Operation Archer team."
The episode of Police Ten 7 will be shown on TV2 at 7.30pm tomorrow, as well as on TV2+1 at 8.30pm.
Anyone with information that could assist the investigation is asked to contact the Operation Archer team on 04 527 2300.
Information can also be provided via the Police Ten 7 show or anonymously via Crimestoppers on 0800 555 111.