From publisher blurb:
Firewall has specialists for everything. There are hired guns who can kill anything, corporate bigshots feeding funds and info to their proxies, scientists studying things most transhumans can't comprehend... whether it's infosec, data smuggling, or just someone who can play the cello, if Firewall could possibly need it, they have highly-trained Sentinels primed and ready to go at a moment's notice.
But none of those guys are available right now. You are.
Something big is going down, and it all starts in your slice of Noctis-Qianjiao. You might not be perfect for the job, but imperfect and nearby will do in a pinch. Not a good time? Tough shit, buddy—you knew the risks when you signed up, and if you don't fix it you're probably fucked anyway. So suck it up, join up with the other Sentinels you've probably never even met, and try not to turn this into a fiasco.