Act of Vengeance (1986) Fact-based story about the corruption that occurred during the United Mine Workers' 1969 presidential elections. Jock Yablonski was a loyal follower of then chief Tony Boyle. That all changed after 80 men are killed in an unsafe West Virginia coal mine and Boyle defended the mine owners. At his wife's urging and in fear of his life, Yablonski launched his campaign. And in fact, he became the target of assassins.