I had a good time reading The Nowhere Thief. The central concept invites comparisons to The StrangeWorlds Travel Agency but there are plenty of differences to that series and I enjoyed the worldsbuilding and plot. 

I did feel that the characters needed more work. The two main characters Elsbeth and Idris were very likeable but perhaps a little underdeveloped, while another character seemed to undergo a sudden personality change solely in order to suit the plot. This is a debut however so I can hope that Ross's character work improves over time, perhaps in a sequel if one is intended. 

Overall this is a fun book that I recommend to both kids and adult fans of middle grade fantasy.