Hardnosed entrepreneur Packer turned cricket on its head, introducing coloured uniforms and taking one-day cricket to the world, ultimately leading to the notorious underarm incident in 1981.
O'Kane took months to perfect the distinctive slingshot action of Thomson, who still holds the world record for the fastest delivery.
Playing a dyed-in-the-wool Aussie cricket hero was a challenge for O'Kane, who grew up with posters of the New Zealand cricket team on his wall.
"He had such a fearsome reputation," he says of Thomson. "He was called the 'sandshoe crusher' and used to do serious damage to batsmen back then."
Another Kiwi, Craig Hall, plays Packer's right-hand man.
Hadlee plays an umpire in Save Your Legs, a movie about Aussie battlers whose club cricket team travels to India to play.
Hadlee says his 30-second cameo took six hours to film and he wasn't paid. "You need a lot of patience. There were quite a lot of sequences. It just fitted in, there wasn't any fees or anything."
O'Kane also played cricketer Bob Blair in the telemovie Tangiwai.