An unfathomable incident introduces a genius engineer to dangerous secrets of the world — and to a woman from the future who's come looking for him. Han Tae Sul, a co-founder of Quantum and Time, is a genius engineer with the highest level of coding skills and outstanding looks that outweighs his engineer fashion sense. Due to his innovative achievements, Quantum and Time is a world-class company, dubbed as "The Miracle of South Korea's Engineering Industry." In reality, Tae Sul has constantly caused his company's stocks to fluctuate after his brother's death ten years ago. One day, he witnesses something unbelievable. To reach the truth, he sets off on a dangerous journey. Kang Seo Hae is a survivor of a future dystopian world. With the survival skills that she's learned from living amongst gangsters and warlords, she travels back to save Han Tae Sul. (Source: Netflix, Newsen)