When you first talk to ShadowChild in her apartment, she will give you a statue to place in Leona Rosolova's office. She informs you that Leona was someone she used to know, and that the statue will mean something to her. However, she does not go into detail about the significance of the figurine. Once you have gained access to the Palisade Blade, make your way to level 3 and find Rosolova's office. Place the figurine on the left hand side of the desk, and ShadowChild will contact you, while also giving you the achievement. As thanks, she tells you the password to Rosolova's computer (which is TrustNo1). Reading one particular e-mail is needed for the Murder He Wrote achievement.