Endless Frontier 4000

Solar system, end of the fourth millennium AD.
Two bounty hunters decide to pull off a small scam, pretending to be friends of a dead rich man. In response, they hear laughter, because even for a dead man it is indecent to have such scum as friends. But this turned out to be only the beginning of the conversation. The heir feeds them with turtle soup and promises, drawing them into his game with unknown goals.
While "up there", among the contentment and luxury, they weave intrigues, deep "down there", among the interweaving of technological transitions and utility networks of life support, the outcasts and those who did not fit into the society of universal well-being, build secret temples for frightening cults.
Ancient Earth, emerging from centuries of hibernation, began expansion into the Solar, pushing through its interests and breaking old trade ties. And on a distant frozen planetoid, beyond the edge of the inhabited sphere of the Solar System, among the darkness of ancient structures of a thousand years ago, the key to enormous power is locked.