The Nelson Trolley Derby is more than just a race down Collingwood St hill in the heart of the sunny South Island town. Run since the 1940s, the annual event is an institution. Thousands line the track as little tackers in the Nippers class, older kids in their Zimmers and Zoomers, and big kids in their Rockets trundle down the road at ever-increasing speeds.
Tony Simpson, a former Nelson local and film director, remembers building trolleys as a kid: "Then we'd be off flying down the hills".
And now, inspired by the races down Nelson's fabled trolley hill, he's made feature film Kiwi Flyer.
"The hill is great, it's right in town, and the derby has an age range from kids around 5 years old right up to adults. So it's just a great family day out and that ethos comes out in the movie. It taps into everyone's childhood - and the thrill of speed," he says.
The film tells the story of Ben (played by Auckland actor Edward Hall), a likeable 12-year-old who's on a mission to win the local trolley derby in memory of his father who died a year earlier.
Made with just a $1.1 million budget it has the look and feel of one of those classic Sunday night films that the whole family would sit down and watch. But with a bit of Terry Teo - remember the skateboarding schoolkid from the 80s? - and tweenage Goodbye Pork Pie-style shenanigans thrown in.
"We set out to make a movie that was charming, although not deliberately, because we just wanted to make a movie that would entertain Kiwi kids and their families."
So there are baddies - and Ben's bitter rivals - in the form of an Aussie family led by devious dad Wayne (played by Mr Beaurepaires, Vince Martin), a chase scene through suburban back yards, and the bad guys getting splattered in poo ("After taking the film to Toronto [the Film Festival], clearly poo jokes travel internationally").
The cast also includes Tandi Wright (Nothing Trivial) as Ben's mum Karen, comedian Dai Henwood as Mr Lumsden, the oddball teacher who has a crush on Karen, and young Auckland actor Tikirau Hathaway as Ben's best friend, Jeff.
Simpson, who has worked in television and film for 25 years including stints on Shortland Street and making kid's telly, had the idea for the film after visiting his dad in Nelson four years ago. They went to the trolley derby - just like old times - and on his way back to Christchurch he got thinking about the diverse bunch of people at the event and the vast array of trolleys.
"There was something so Kiwiana about it, and a bit nostalgic with the kids and their dads and the trolleys," he says.
The rival trolleys in the film are very different; the "Aussie Flash" is a sleek, pristine-looking beast whereas Ben's home-made "Kiwi Flyer" is makeshift and dinky but fast (especially when they borrow some fancy aerodynamic wheels from Mr Lumsden's racing bike).
"We wanted to make it the old home-grown cobbled-together-with-number-eight-wire trolley versus the sophistication of the Aussie Flash. It was the Kiwi battler idea. And you need a great underdog in a movie to come through to create a good hero," says Simpson.
The rivalry between Ben and the Aussies is based on Simpson's own real-life competition with a mate of his. "They came out with this fantastic flash trolley called NAC," he remembers, "and they blitzed the field because everyone else had tomato crates with string. And that was the first vestige of corporate corruption [in trolley racing] at the highest level," he jokes.
"And so, to make a great movie you need some good baddies, so we picked on the Aussies."
On the flipside is Ben. While he lies to his mum and ropes Jeff into helping him build a trolley behind her back, he's a good-hearted, wise young fella.
"We just wanted kids who were watching to really connect with him. We all get up to mischief, and we all want to do things our own way, and there are not often reasons for it, and they don't ingratiate themselves to their parents in that way either, but kids need to explore things and answer questions for themselves.
"And we had to balance Ben to not be too cheeky, not too devious, but still have an honesty to him as well. Because what was important to the movie was a subtle delivery of morals and values. We wanted kids to come out of the theatre and say, 'Yeah, you have to do the right thing and give it your best'."
Not that it's preachy and condescending. And although the film sits on the fence when it comes to winning versus giving it a go, there is no question that Ben wants to win the derby because he's doing it for his dad, and he will go to great lengths to make it happen.
"The Aussies don't have much trouble with winning at all costs. They are foot on the throat. But it's something Kiwis have a problem with. We decided to present it [in the film] as doing the right thing and giving it your best even if you don't get the gold medal. But you still want them to win."
Simpson says given the relatively small budget the film would not have been possible without the support of the Nelson community. Many of the actors were local kids, including Myer van Gosliga and Doug Colling who play bad guys Shannon and Shayne, and there are cameos from well-known locals like mayor Aldo Miccio and Pete Rainey, the founder of long-running high school music competition Smokefreerockquest, as an irate motorist. Also helping to bring the film in on budget were members of the Nelson Trolley Club who fronted up with their trolleys during race day filming and having the backing of the Nelson City Council.
For Simpson, and co-writer Andrew Gunn (What Now, The Beginners Guide to Space Travel), making the film was a chance to document and bring to light one of the country's many unsung events - and it's something they'd like to do more of in the future.
"I think we need to be telling more of our great stories to Kiwi kids because they would love them," says Simpson.
What: Kiwi Flyer, a new local film inspired by the Nelson Trolley Derby
Who: Director and former childhood trolley enthusiast Tony Simpson