Duncan Sew Hoy is determined to return his great-grandfather's remains to China.
The coffin containing Choie Sew Hoy was lost when the SS Ventnor sunk off the Hokianga coast more than 110 years ago.
The Dunedin-based Chinese pioneer had organised a mission to return the bodies of Chinese miners - his second such shipment - back to their homeland in Guangdong, China, for reburial.
However, Mr Sew Hoy died a year before the shipment and his remains were in one of the 499 coffins aboard the lost ship.
The Sew Hoy family were the only known descendants, as the vessel's manifest went down with the sinking of the ship on October 28, 1902.
That story, along with the emotional journey of the Sew Hoys to complete their ancestor's journey, is the subject of a new documentary from Dunedin television company NHNZ.
Duncan Sew Hoy (79) told the Otago Daily Times he knew nothing of the sinking until he became involved in another documentary on Chinese miners in 1997.
"I read about it and just felt so emotional.
"I felt that as I am the direct live descendant of my great-grandfather... and I felt the legacy had fallen on my shoulders to complete his journey, and that of the 499.
"That was when my dream started. But this dream is worse than mission impossible."
However, his goal was advanced by a chance meeting at his Golden Harvest restaurant with NHNZ executive producer Alan Hall. As a result, Mr Sew Hoy and son Peter have become the focus of the documentary The Lost Voyage of 499.
That hour-long documentary screens on Maori TV at 9.30pm on Monday, and is likely to inspire a follow-up. The Royal New Zealand Navy had confirmed it would assist in attempting to locate the wreckage next month, Mr Hall said.
Mr Sew Hoy believed the tightly packed and sealed hold of the ship -- sunk some 16km off the Hokianga coast -- contained 489 coffins of South Island-based gold miners, the majority of whom were from Otago.
The remaining 10 coffins of North Island-based Chinese gold miners could not be stored in the hold, and were likely to be the coffins washed up ashore and buried by local Maori.
"So they became Kiwis forever."
Mr Sew Hoy said he hoped to have the remains of the South Island men returned to their ancestral homeland, and had already talked to officials from both countries to gauge support.
"The 499 are past heroes; they worked hard and made money for both countries."
Mr Hall said he was particularly touched by the cultural similarities between the Chinese and the local iwi whose ancestors buried the remains that washed ashore.
The documentary followed the Sew Hoys' journey to China and to the Hokianga where they met people of the Te Roroa and Te Rarawa tribes, but their journey was by no means over, Mr Hall said.
"It would be a tremendous first step in Duncan Sew Hoy's dream to return his ancestor's remains home to rest in peace forever."
The documentary was a co-production between NHNZ, China Intercontinental Communications Centre and China Central Television, and was made with the assistance of the New Zealand Government's screen production grant, Maori Tourism and New Zealand Ministry of Foreign Affairs.