Most people have a family heirloom they've been trusted to look after for future generation. Very few heirlooms will be 150 year-old submarines. But that's the exact situation Pete Sparrow has found himself in. Pete has been involved in the restoration of a 10m-long, iron-plate Platypus submarine, which was built by his great-grandfather Joseph Sparrow in 1873. The partially restored sub will be unveiled in its new enclosure in Middlemarch, about an hour from Dunedin, this weekend. Pete joins Mark Leishman on Nights.