Rukia returns to Soul Society concerned about Byakuya, but he's still missing according to Renji. Ichigo and Yoruichi then arrive to Soul Society, and Yoruichi warns Ichigo to be careful and beware of his own Zanpakitou. While Rukia continues wandering around thinking about her brother, she happens to come across Sode no Shirayuki, her Zanpakutou, terrorizing some Shinigami, so she steps in to intervene. Sode no Shirayuki makes it a point to say that she's now free and can do what she wants, and during battle, she shows that Rukia has a hard time fighting without her Zanpakutou techniques. Rukia tries to counter with a kidou spell, but Sode no Shirayuki has no problem protecting herself with a barrier of ice. As she dodges the counter-attack, Rukia wonders why Sode no Shirayuki seems to hate her, and she remembers her joy and times shared practicing her techniques in front of Kaien many years ago.
Sode no Shirayuki is then about to finish her off with the Hakuren technique, but Ichigo steps in and saves her. Rukia doesn't think that Ichigo should be here when they don't know what's behind the Zanpakutou uprising, but Ichigo feels that it's fine and that they just have to find out what that reason is. Ichigo, already in bankai form, then engages Sode no Shirayuki in battle, but she soon notices that he's hesitating to attack her. She has no such reservations towards him though and uses the full extent of her ice powers. Rukia tries to take advantage of this by attempting a sneak attack, but Sode no Shirayuki senses it coming and easily blocks it.
Not giving up, Rukia has Ichigo back down since this is her fight, and Sode no Shirayuki admits that she hates her and that her goal is to deprive Rukia of everything important to her. Rukia responds by acknowledging that her Zanpakutou is free now, and she asks her to calm her hatred. Sode no Shirayuki is surprised to hear this, and she's even more surprised to see Rukia use another kidou spell to bind them together. Rukia is ready to relinquish everything and uses a final kidou spell whose explosion envelopes both of them. Her farewell causes Sode no Shirayuki to want to reach out to her again, but she's pulled back by Muramasa. His appearance also stops Ichigo dead in his tracks and distracts him from checking up on the now unconscious Rukia. When Ichigo questions who he is, Muramasa reveals that he's a Zanpakutou.