When the CEO of a successful surf company is murdered, Kono revisits her past; Five-0 is thrown into the varied but interconnected worlds of North Shore surfing.

It's Christmas in Hawaii, but instead of celebrating, Five-0 is negotiating a hostage situation when the man who killed McGarrett's father resurfaces. The murderer, Victor Hesse, threatens to detonate an explosive that he's strapped to Chin Ho's chest.

When the sole witness in a high-profile murder case disappears, Five-0 must head into the jungle to locate and protect her from assassins who are closing in fast.