Helen, a London ad executive, is fired from her job and rushes out to catch a train, but, as she runs down, her life suddenly splits off. In one version she catches the train; in the second, she misses it. Her whole life changes in that one second, and the rest of the film depicts what happens in each scenario.

What if one split second sent your life in two completely different directions?

Helen, a London ad executive, is fired from her job and rushes out to catch a train, but, as she runs down, her life suddenly splits off. In one version she catches the train; in the second, she misses it. Her whole life changes in that one second, and the rest of the film depicts what happens in each scenario.