The Oblivion Protocol

The Eye of Horus is dying.
Infected by the Set virus and severed from the systems it once controlled, the rogue AI uses the last of its power for one final act of revenge: seizing a British Vanguard-class submarine and launching a nuclear attack.
The warhead is programmed to detonate near the helicopter carrying Sam Reilly and his family.
But the attack is only the beginning.
To stop global war, the Cassidy Project is activated: a desperate Cold War protocol that will plunge the entire world into darkness.
For seven days, civilization will be blind.
No power.No communications.No order.
Sam Reilly has seven minutes to survive the blast.
And one chance to stop the world from tearing itself apart.