The new age promised by the original prophecy is taking a sinister shape. Around the world, entire continents are ravaged by famine and battered by biblical weather...

A sudden plague sweeps through the Citadel, killing many of the brotherhood within its ancient walls. Some say it is because the Sacrament was stolen, or worse, destroyed. Others say it is simply a test from God. When the lone surviving Sancti returns to the mountain, he tells them all: the Sacrament must be regained.

Released from prison, Gabriel Mann goes to the hospital to check his mother Kathryn and Liv Adamsen have survived the explosion which rocked the mountain. Kathryn asks her son what he saw in those upper reaches of the Citadel. Gabriel cannot be sure of what he witnessed - only Liv knows for certain. But she is already gone.

Liv waits to board a plane back to the USA, filled with an unbearable urge to go home. In the terminal, she listens to the babble of voices in many languages. She can understand every word of them all. A murderous rage consumes her if any man so much as raises his voice. When she reaches the burnt-out shell of her destroyed apartment, she knows this is not the home she was seeking.

Followed by the Church's 'Watchers', Liv cannot stay safe for long. She suffers from blackouts - always announced by a word whispered in a language long dead. She knows Gabriel is the only one who can protect her and might understand what is happening. But back in Brazil, Gabriel has no idea how to find her.

Both their journeys will span the globe to find the same answer. What awaits them is another terrible truth - one which will shatter their bond and change the world forever...