The Voynich Cypher — Russell Blake

When a sacred relic is stolen from its subterranean guarded vault, Dr. Steven Cross, amateur cryptographer, becomes embroiled in a deadly quest to decipher one of history's most enigmatic documents - a 15th century parchment written entirely in unbreakable code; The Voynich Manuscript. Stalked by secret societies, and aided by the daughter of a murdered colleague, a trail of riddles catapults Cross from England to Italy to the Middle East, where a Byzantine web of ancient secrets leads him to a revelation so profound it will change the world order.