The Vessel, by Taylor Stevens

In Taylor Stevens 2013 novel The Doll, Stevens's super-heroine Vanessa Michael Munroe helps take down a human trafficking ring--that is, after she is captured by it.  The problem is, she's not satisfied.  One of the ring leaders is still out there.  In the 2014 novella The Vessel, Munroe meticulously plots--and exacts--her revenge.

The Vessel is a stand-alone story, with enough back-story to give some context for first-time readers of Stevens's books.  But it is best enjoyed in the context of the series, especially as a follow-up to The Doll.  Munroe is smart and stealthy, chameleon-like in her ability to blend in and sneak around.  Whether staying the background to gather intel, or slipping back into the background after amassing a large body count, she leaves no trace. 

Despite her vicious, murderous, revengeful streak, I root for Munroe because she is driven by compassion and justice.  Like any good action hero, she is driven by a selfless pursuit to make wrongs right, seeking no recognition or gain for herself.  If you read The Doll and ended up a little disappointed that Munroe was not able to get all the bad guys, pick up The Vessel.  The bad guys get what's coming.