The collision of sport and politics is the focus of a new film set to premiere at the New Zealand film festival this week.

By the Balls takes an in-depth look at a turbulent time in our rugby history: the 1986 Cavalliers tour to South Africa.

And then add the bombing of the Rainbow Warrior and protests against nuclear testing in the pacific, which added to the tension of upcoming matches against the French.

Directed by Simon Coldrick and Charlotte Purdy the story is told through the eyes of the players with key players of the time involved in the making of the documentary.

Former All Black captain David Kirk was one of only two players that refused the payments on offer for the rebel tour.

Kirk and director Simon Coldrick joined Francesca Rudkin to discuss how the movie came to be and reflect on a turbulent time in our sporting history.