When they flew Casey into the hospital at Nha Trang, the medics were sure he would die. That he didn't was only the first surprise. The second, and bigger one, was that Casey had been fighting for two thousand years, ever since that day on Golgotha when he thrust his lance into the side of the man on the cross. "Soldier, you are content with what you are. Then that you shall remain until we meet again." Thus does Casca's journey begin, a man who cannot die, does not age, and knows no skills but those of battle.

Casca, also known as Casca Rufio Longinus, is a series of novels created and written by author Barry Sadler in 1979 who would go on to write one more Casca novel before a series of ghost writers would pen the remaining stories.

The series involves the ongoing life of a soldier in the Roman legions who is condemned by Christ on Golgotha for driving a spear into him. For his efforts Casca was doomed to wander the Earth aimlessly, always as a soldier.

Casca was first introduced in 'Casca #1 The Eternal Mercenary'. Here Jesus condemns Casca by saying: 'Soldier, you are content with what you are. Then that you shall remain until we meet again. As I go now to my father, you must one day come to me'.

Casca did not initially understand what had happened to him until he was condemned to work in labor mines over a 30 year period. There he slowly discovers that he does not age and cannot be killed or seriously wounded. He learns that he is immortal, although he can feel all pain inflicted on his person.