In AD 59 one of the towns in the Roman Empire, Colonia Agrippina–present day Cologne, Germany–is running out of fresh drinking water. The Senate in Rome assigns Amulius Atius Vitellius, one of their best Prefects of Engineering to locate a new water source.
Before he leaves for Agrippina he is converted by Apostle Paul to Christianity. On the way his new found faith is tested severely. He expects to find God’s help but instead encounters harsh winter weather, tortuous roads, disease, bandit attacks, accidents, and treachery.
In Agrippina he faces more problems: rugged terrain, foul weather, and hostile natives, but he feels they are insignificant compared to what he suffers inwardly. He has a difficult time maintaining his faith as a Roman citizen surrounded by false gods. He thinks he should be spreading Christianity among nonbelievers but realizes if he were to do so he could never complete the water project. Rome would condemn him to death. His difficulty is further compounded when he falls in love with a pagan girl, Aine from the Baltic. He is an esteemed Roman citizen; she is a slave. Amulius knows that Living Water is their only salvation.