Sisyphus is a really good time travel action thriller with a nice slow burning romantic story. The drama has a great cast and they did a good job bringing their characters to life. The leading female character, Kang Seo Hae (played by Park Shin Hye), a survivor of a future dystopian world, teams up with Han Tae Sul (played by Jo Seung Woo), who is a genius software coder IT engineer and a co-founder of Quantum and Time, a highly esteemed company in South Korea's Engineering Industry, to try to save the Korea from a nuclear attack. The drama has action, mystery, and some romance. Although the drama’s development is not perfect, it is very entertaining. Enjoy it!