Hive by Tim Curran

Nothing stays buried forever at the Pole.
In the frozen wastes of Antarctica, a research team discovers the frozen remains of an alien race in a mountain cave. They are dead, but not dead enough.
At the bottom of a sub-glacial lake beneath the ice cap, a prehistoric city dating from antiquity is found. And what has waited there for hundreds of millions of years, has been awakened.
These two events are the catalyst in an ancient conspiracy that will culminate in the extinction of the human race.
Evil has waited forever.
But it waits no more.