A YOUNG MAN DISAPPEARS in the California wilderness. He leaves behind a gold-flecked rock and a vial of toxic mercury. He is a misfit in the modern world, a throwback to Gold Rush days.A venture capitalist--whose gold country is Silicon Valley--hires forensic geologists Cassie Oldfield and Walter Shaws to track his missing brother.Following one of the 'lost rivers' of the Mother Lode, the geologists plunge into the dark history of the legendary lands, into the dark past of the brothers, into a poisonous sibling feud that threatens both lives and the land.And they are not the only ones on the hunt. -- All books in the series are complete novels and can be enjoyed in any order.