Evil Under The Circle (G1: The Guardians‪)‬

A chance find of a tunnel under an ancient stone circle leads to a terrible secret, hidden millennia before. As terror strikes, and evil consumes, only one group can help: the Guardians. Their elite team, G1, arrives and must overcome the ancient evil. If they fail, then the very world will be destroyed.

Joined by unexpected allies, G1 face one of the greatest challenges their organisation has ever encountered, and there's no guarantee that they will survive!

A novelette.