During the Qin Dynasty, general Hwang Sung Kyong is tasked to escort the Korean princess Soo-Min from Korea to marry the Qin emperor in China. Along the journey, a Korean warrior attempts to seize her back but Hwang saves her. Soo-Min falls in love with Hwang and displays her affections for him openly, but Hwang keeps his honour by rejecting her and successfully completing his mission. The Qin emperor becomes critically ill later and he sends Hwang to find the immortality elixir, the only thing that can save his life. The guards escorting the elixir are ambushed by rebels on the orders of the treacherous prince and chancellor. Hwang hands over the elixir to his deputy Nangong Yan and dies in the ensuing battle. Although Nangong manages to hand the elixir to the emperor, the traitors accuse him and Soo-Min of treason and force them to consume the elixir, condemning them to imprisonment in the Qin emperor's mausoleum for eternity.
In the present-day, Ryong, an archeologist, is the reincarnation of Hwang Sung Kyong, as he often dreams about his past life. One day, his friend Liam invites him on a quest to hunt a rare material that can create a field of zero gravity. They travel to a floating tomb of a Dassar king in India, where Ryong finds a sword and has a recollection of a duel he had with the king in his past life. Liam accidentally removes a piece of the material and the zero gravity field collapses, destroying the tomb. Liam manages to escape but Ryong leaps off a cliff and falls into a river. He loses consciousness and drifts along until he is saved by a woman named Amanda. Later, Amanda brings Ryong to see her uncle, a Kalaripayattu guru, who enlightens him about his past and future. Ryong succeeds in returning home safely and he delivers the sword to the National Museum of China as a national treasure. His action angered the leader of the secret organisation that has been funding Ryong and Liam's treasure hunt.
After extensive research, Ryong and Liam conclude that the anti-gravity material is actually fragments of a meteorite that fell to Earth during the Qin Dynasty. They find the exact location of the Qin emperor's mausoleum, concealed behind a waterfall. The massive tomb contains the strongest fragment of the meteorite, which is powerful enough to make the tomb become a floating palace. Ryong meets Soo-Min and Nangong Yan inside the tomb and they mistake him for Hwang Sung Kyong. Just then, a group of intruders led by the organisation's leader enters the tomb and they attempt to seize the Soul Edge, culminating into an aerial fight between the two parties. Liam accidentally breaks the balance of the field after removing a piece of the meteorite and causes the tomb to collapse on itself, and dies after drowning in the mercury river. Ryong escapes from the collapsing tomb, asking Soo-Min to come with him, but she refuses after realising that Ryong is not Hwang Sung Kyong. From the next day, Ryong is seen writing a book about his experiences, which he dedicates to Liam.
Before the film ends, In the few month later, Ryong is held in the bookstore to giving his autograph to the fans. Meanwhile, Ryong saw a girl in coat with the similar faces of princess Soo-Min and besides her was another similar faces of Seong Mi-Na in jacket, Yun-Seong in T-Shirt and Han-Myeong in tuxedo, queue up behind of them. Ryong was mistaken that they were not from the part of the legend, but in the present-days.