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4.0 16
by Jeremy Robinson, Sean Ellis
Strange things have always happened in the Superstition Mountains of Arizona... Bizarre lights, reports of cave entrances that appear and then vanish, hundreds of mysterious disappearances...and rumors of monstrous creatures that inhabit a labyrinthine underworld.

When a terrifying accident on an Arizona highway leads to a military exclusion zone and a cover-up of

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123California Appellate Decisions 4.1 out of 5 based on 0 ratings. 16 reviews.
Anonymous More than 1 year ago
This one was barely tolerable. Robinson seems not to be so great with novellas- or maybe just not writing with a partner. It didn't read much like a Robinson book. There was way to little in the form of explanation and too much action. I want a more balanced book. I agree with the other reviewer that this read like a teen book. Stephanie Clanahan
Kelnyg1 More than 1 year ago
A fun second addition to the King series. Filled with monsters, friendship, the underworld and the odds stacked against him, King is once again proving that the odds don't apply to him. Robinson & Ellis always delivers fast-paced, enjoyable fun
Anonymous More than 1 year ago
CarolPixieBrearley More than 1 year ago
Another excellent Sigler book by Jeremy Robinson. Callsign: King - Book 2 - Underworld brings yet another mysterious foe and more thrilling excitement. Taking all my willpower to take a break from starting book 3 to write this review, cannot wait to see where King goes next and what he ends up going against.
Dustino More than 1 year ago
Call Sign: King, book 2: Underworld is the second part of the Brainstorm trilogy.  Fast paced and action-packed, this novella is hard to put down.  Just like all the others!  Try it out once you've read the rest: Prime, Pulse, Instinct, Threshold, and the Call Sign novellas for King, book 1, Queen, Rook, Bishop, and Knight-in that order.  Now onto Call Sign: Deep Blue!
Rianrenee More than 1 year ago
The Chess Team books are a blast to read and I loved each of the Callsign books.  Get to know each character a little better with a great story.  You can't go wrong with Jeremy Robinson's books, check them out!
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Anonymous More than 1 year ago
Giant, cave-dwelling numismatists wearing hair shirts.
Boatsm3 More than 1 year ago
Awesome.....great book...
Anonymous More than 1 year ago
Keep the excellent books comming. Everyone of his books are page turners. Once I start one I cannot put it down until finshed.
jmn246 More than 1 year ago
This story might be okay for a teenager, but for an adult it was pretty bad. I would compare it to an adventure movie where the hero is being shot at by 100 guys, but manages to save the day. Yeah right! Even though the subject matter is unbelievable you need to believe that it could happen. This book just didn't deliver that for me.