Another good fun adventure but similarities to #1 forecast the problem of this, the last, and the next two books, which is mainly too much adrenaline, too little downtime and human interaction. 
 All the Verus books are quick reads (at least up to #4, haven't read #5) but they're like watching action movies in book form. Although Jacka promises a rich character, he delivers more Boss fights than quiet moments. He doesn't take the time to give anyone around him a rich enough internal life. 
 Kudos for Verus's path through these first four books on coming to grips with his past, but points off for not really committing to any character other than Alex. 
 I really liked the books so far, especially #1 and #2 (with #4 then ahead of #3) but I wish Jacka would give us more than "this guy fights real cool, so let him fight over and over and over and over"