Mary grew up on the Hauraki gold fields having emigrated from Scotland with her family. As the daughter of a mine manager she enjoys a charmed life and teaches piano, sure that music would be the one thing that defines her.
Archie Wright came to Waihi to be near his brother after his wife died in childbirth. With two small children to provide for he accepted a job as a stationary engine driver, a position well below the mine manager job he left in Ballarat.
When the engine drivers form a separate union Archie does not join them and the action leads to the longest strike in New Zealand's history.
Amongst the turmoil Mary and Archie fight for the rights of the strikers, he as a union representative and she as a Scarlet Runner. But their message is not well received and the government clamps down heavily on the strikers by sending more and more police to the town as the strike drags on.
Archie finds himself opposing his brother and Mary causes grievous upset by defying her father. Her family becomes the target of mischief making which has unintended and fatal consequences and which forces Mary to question her loyalties.
Mary has a conviction that in her eyes equals that of her mother, Emily, who fought for temperance and won. Emily's legacy sits heavily on Mary and she sees the strike as her platform for social change. She is a sponge for Archie's socialist philosophy and with her Scarlet Runner accomplices ensures the aims of the strike gain sympathy from men and women alike.