In the 1980s, Anna, a Czech sprinter, starts training for the Olympics. After she collapses during training, she learns she is being given steroids and decides to stop using them until her mother helps the coaches give them to her.

Iconoclastic, take-no-prisoners cop John McClane, finds himself for the first time on foreign soil after traveling to Moscow to help his wayward son Jack – unaware that Jack is really a highly-trained CIA operative out to stop a nuclear weapons heist. With the Russian underworld in pursuit, and battling a countdown to war, the two McClanes discover that their opposing methods make them unstoppable heroes.