On Holy Mother Mars, the [terraformed] climate is failing and mankind seems doomed. The cities of Mars in the mountains are crowded, while the lakes and oases of the lowland deserts are drying up. Green Mars is increasingly becoming a red and desolate Mars. What about ancient legends that Mars was once a blue world with fresh, frothing seas? Where did the oceans go? Can they be retrieved? Young monk Brother Farr of Mars is startled by a sneak visit into Graniston Domes by wild-eyed exile Shan the Heretic, who tells of the looming assassination of the Popess. Shan starts to reveal other heresies to Farr-for instance, that there really was once a home world, and that Earth is more than a myth or a pious scripture paradise. Moments later, Shan is killed by temple police, and his secrets die with him. But the seeds of question, of rebellion, of searching for truth have been awakened in Brother Farr, and there is no turning back as he begins a journey beyond time and space on the Time Train system built by long-ago aliens. An assassination of the Holy Mother-a murder of such magnitude will throw the entire world into turmoil unless the renegade Duke Balesso can be stopped. [Contact with Earth was lost ages ago, and the Mars humans believe they were brought to their holy planet by gods]. Farr begins an epic journey fraught with danger, intrigue, and ancient mysteries. His quest for the lost seas of Mars, takes him through the valleys and kingdoms of Mars, and into a transit world (the Temporale) outside time and space. Farr is on a quest to learn the truth about Mars, himself, and the human race. He gets more than he bargained for as he learns of the players (some human, some alien) in a saga spanning eternally many times and infinitely many spaces. Besides Brother Farr, we meet his tragic childhood love Sudie; a stern abbot hiding family secrets; the military priestesses Trinity and Singularity; a doomed king; a pair of gloriously charismatic Martian lady popes; and a host of other strongly crafted, breathing, and engaging characters. Brother Farr travels to the past and future, meeting the historical H.G. Wells in Victorian Gaslamp London. Farr's seemingly hopscotch journey takes him eons back in time to learn a fundamental secret about Mars that will change mankind forever. Along the way, he is tormented by the loss of his one, early love in life-and questioning of his vows. In the far distant future, at the end of time, he visits the City of En--whose agents are desperately tweaking and working the Temporale to save their city. Cosmopolis, or the City of the Universe as it is known among myriad other names, is in danger of disintegrating as time dissolves around it due to a long-ago temporal war. This epic struggle, spanning the Motherverse with its infinite spaces and eternal times, is the framework within which the Time Train series takes place. Ruthless, daring, and fiercely dedicated agents of the Temporale-often at deadly odds with each other-conspire to save the city at the end of time, no matter what it takes. If Mars, the home of mankind, is to be saved, Brother Farr must unlock the secret of the Seven Lenses, in which the fate of Mars' primordial oceans is inextricably bound.