Rating: 3.5 stars rounded to 4
By this point in the series, there really isn't much new material I can add to the review. If you liked Death's Head and Equinox, then Scorpio should be right up there with its predecessors. This installment brings in an old comrade from Death's Head (about time!) and also has more involvement with Harry Del, who took the back burner during Equinox.
My biggest gripe with Scorpio is that it didn't bring anything new in the relationship between Stone and Jarrat. While book one established the relationship and empathy and book two had the two MCs working with their new found connection under observation from higher-ups, Scorpio only hinted at possible problems with their empathy and what this could mean for the future of NARC. The relationship, while still containing moments of intimacy between Stone and Jarrat, pretty much took second place behind the actual conflict in Thule with Scorpio (even the empathy played little role in the investigation asides from the brief undercover mission). While the investigation and conflict in itself was superb, I kind of wished there was more material to explore in the MCs relationship or their empathic connection.