What I've read: Ch. 1 - 4. I'll try to minimize spoilers, but, you know, beware.
Ash wakes up on the floor of an old, dusty shed with his worried dog, an old muscle car, the keys and some cash in his pocket, and no memory of how he got here. He soon finds himself going up against Andres, the Big Bad of the story, and Andres's goons. They want a mystical golden spider statue that Ash last remembers seeing when he was a boy. With his dog Moolah, Ash makes a daring escape from their clutches and drives off in the stolen car to get in contact with his brother who confirms it has been two weeks since this whole thing started--two weeks that Ash doesn't remember.
They say not to start your story with your protagonist waking up. They say waking up with amnesia is an even more egregious cliché. The Spider Thief does both and does it well, partly because Ash doesn't have time to languish in confused introspective and partly because I'm a sucker for a good mystery.
So it doesn't exactly open with a bang, but the bang comes relatively quickly and it's fantastic. The action scenes are the best part so far. They are kinetic with a crisp narrative and vivid details of the car, the terrain, and each dangerous setting.
Ash is as yet defined by his interactions with his dog and other hints that he's the Good Guy. His personality is obscured by the heightened state of urgency which necessarily reduces him to just adrenaline and survival instinct. At this stage, the plot is moving him instead of the other way round.
The clues about how he got in this mess are piling up, and I'm just letting most of them lay where they landed until we get more information. As for the Spider, we know touching it results in amnesia and a skin rash (which Ash has on one hand.) So, Ash must've had the spider recently. Where is it now? What else can it do? What does Andres want it for? And how did Ash get caught up in this mess?
We shall see. Spoilery discussion is welcome in the comments, if you've read The Spider Thief, are reading along, or just curious.