Newly orphaned Henrietta is welcomed into a secret agency and trained, along with her sibling Jose, to become a lethal assassin.

Feeling responsible for her inadequacies, Jose tries to learn what Henrietta needs to help her become a successful assassin.

The Social Welfare Agency gives Rico a new body; Rico encounters a boy who makes her question who she is.

The tension between Hilshire and Triela could endanger their mission of protecting Mario Bossi, a retired criminal who's become a government witness.

Captain Raballo accepts a job with the Agency. However, when he's paired up with Claes, he begins to wonder if his needs justify the pain he must inflict on the young assassin.

Jose and Henrietta are sent to stop notorious terrorist Enrico Berdini from acquiring an explosive device and attacking Rome.