Double Trouble.

They're the devil others fear. They're the danger they didn't dare cross paths with.

The twins, Park Seo Yeon and Park Seo Yoon come from an influential family, and with a wave of the twins' hands, a famous company can turn bankrupt.

They're also good-looking, but then, look didn't define it all, it is character. The twins were famous for their notorious behaviors.

And coupled with them being a reflection of each other, they were able to go scot-free!

The older sister, Park Seo Yeon was very protective of her younger sister, taking the blame for everything she did wrong, but no one knows what kind of life she was exactly living, going to the Internet cafe, car racing, and so on.

But what happens when she decided to get selfish for once?

She liked him and he liked her but what can the older sister do when her younger sister took a liking to the same man?