Young Terry is orphan again by his grandfather. His father an inventor was killed during the great war, and his mother an ancient mayan princess from the city under the north pole, who died shortly after his birth. At the reading of the will, young tery finds out that the majority of the granfathers wealth is either donated to a museum or put in a trust for the boy.
Terry is sent to live with his aunt, who he has never met. She shows up at the will reading as a mysterious and somewhat sinister figure. The Aunt is to become his custodian. She is a WWI vet/spy turned commercial treasure and bounty hunter and people hire her and her tiny team to hunt for treasure of all types, which leads her into contact with spies, Nazi's, super scientists, cryptozoological monsters and elder gods.
She wants a book or a relic from the grandfathers collection, but can’t access the resources of the grandfather without the boys direct intervention.
There are secrets buried in the grandfather research and books, and the aunt needs the boy to access the materials.
The grandfather died of mysterious circumstances and was heavily involved with an adventurers society who hunted the same goal he did, the central mcguffin, a great treasure, a tremendous power, guarded by a lovecraftian horror. Within the adventurers society there were various factions, some of which opposed his research for one reason or another.
The aunt with the boys help discover clues to find the great treasure.
They are pursued by members of the secret society who want the treasure power for themselves, and others who wish the mcguffin to never be discovered.
Their chase leads them around the world, and eventually to a series of turquoise lined tunnels beneath the andes mountains, where they must face a lumbering lovecraftian horror, to get the treasure, in the form of an ancient meteorite of alien technology and prevent the baddies from using it to control the world.
There will also be yeti like under the north pole and giant jelly fish and of course Penny Dreadful the teenage pirate queen and her band of grizzled lesbian cutthroats, some pre WWII nazi’s, a super scientist and spy types.