On the northeast coast of Northern Ireland is a peninsula once known as Magee Island where, so it's rumoured, supernatural forces still exist. Amongst the sparse, rural population there are a few outsiders.

Jim Corcoran, a former special forces sniper who served in Afghanistan, also worked for the "Bureau", a secretive UK government organisation that carries out covert operations across the world. Now "retired", he lives on Magee Island – watched and supervised by a minder whose job it is to make sure Jim is not at risk and that he poses no risk to anyone else.

But Magee Island has a violent history, and perhaps there are forces still at work that may threaten not only the local population but also, ultimately, the whole world.