Third entry in the excellent Forerunner Sage series of novels by Greg Bear, set in the Halo universe has been revealed. Entitled Silentium, book will be released on January 8th, 2013 in hardcover, audio and e-book.
For the impatient, here's the official synopsis:
In Halo: Cryptum, Greg Bear began a three-book arc set in the era of the Forerunners, the ancient and enigmatic creators and builders of the Halos, which continued in Halo: Primordium. Now, in the last years of the Forerunner empire, chaos rules. The Flood—a horrifying shape-changing parasite—has arrived in force, aided by unexpected allies. Internal strife within the ecumene has desperately weakened Forerunner defenses.
Only the Ur-Didact and the Librarian—husband and wife pushed into desperate conflict—hold the keys to salvation. Facing the consequences of a mythic tragedy, one of them must now commit the greatest atrocity of all time—to prevent an unmatched evil from dominating the entire universe.