From Dungeons to Daylight
It's the sixteenth century. Phillip is born into royalty. When the time is right, he will become the king of Farley. The king's right-hand man, Cormac, has a son on the same day Phillip is born. While still babies, Cormac decides to kill the king. He then switches the babies so that his own son will eventually become king.
At the age of sixteen, Phillip is thrown into the dungeon. For three years, he is a whipping boy, receiving punishment each time the imposter king gets into trouble. With help from Magnus, a fallen knight who also ends up in the dungeon, the two plot their escape. Once they're in true daylight, Magnus realizes the boy he's been imprisoned with is the rightful heir to the throne.
They decide to form an army and gain back the kingdom. Before the plan can be carried through, however, Phillip falls into a deep sleep. His soul leaves and ends up in the twenty-first century in a completely different body.
Laura, whom he's fallen in love with, and James, his new friend, help Phillip get back to his kingdom. They figure out a way Phillip and Laura can go together, but once they accomplish this task, they're in bodies neither one recognizes.