Here is the Back Cover Tex from his website:

A hunt for a treasure becomes a Quest for the truth

960BC Solomon’s Temple is completed.

70AD Fall of Jerusalem and the Temple Treasure is Lost

1119AD The Knights Templar tunnel under the Temple Mount. Nine years later they find what they have been searching for and return to France. They become the richest and most powerful order the world has known.

1446 Sir William St Clair builds Rosslyn Chapel.

1891 A penniless priest of the small French village of Rennes-le-Château, discovers a parchment hidden in his church – it turns him into a man of great wealth.

1952 The Copper Scroll is discovered in a cave in Qumran. It is a Treasure map believed to have been written around the time Jerusalem fell.

All are connected Part of a Secret buried for centuries.
A secret many have been searching for without success.
Ancient Families, Secret Orders, innocents wronged. All have suffered. All seek revenge. The Secret will give it to them. They just have to find something that went missing over 2000 years ago.

Present day Ben Hammott enters the hidden catacombs beneath Rosslyn Chapel. He discovers a secret hidden for centuries. They are coming to claim it.