Whereabouts of His Left Arm: The Struggle for Trost, Part 5

The Left Arm's Trace is the ninth episode of the Attack on Titan anime. It is produced by Wit Studio and Production I.G. This episode introduces the several members of Survey Corps in action against the Titans while Eren and others face the soldiers in an attempt to prove that they mean no harm to humanity.

Summary
One of the reasons why the Titan's attack on Trost District claimed so many soldiers' lives was due to the absence of the elite soldiers of the Survey Corps. Back to the day of the departure of the Survey Corps, along with the townspeople, Eren, Mikasa and Armin watched their departure. One of the townspeople spots Levi, and then says that in battle, he is worth as an entire brigade. Levi, hearing this, gets a little irritated. Hange Zoë makes a joke that they would be heartbroken if they knew how much of a clean freak he was.

Before leaving, Hange imagines what kind of Titans they will see. She hopes that they'll meet some abnormal ones. Levi comments that he can already see one which makes Hange searching around. Levi then pats her and says to her that the abnormal one is right here, in front of him.

The soldiers entrusted with the mission this time are mankind's best and brightest soldiers. Even so, when troops advance into Titan's territory, the casualties still exceed 30%. While out for the mission, one of the soldiers is caught by a Titan. Half inside the giant's mouth, he threatens him, saying that humans will overthrow them, particularly Levi. As he says this, Levi shows up and attacks the Titan, killing it. With reinforcements arriving, he orders Petra Ral to take care of the wounded. He then orders the reinforcements to take the right flank, while he takes the left.

Elsewhere, Hange seems to be enjoying the mission. She confronts one of the Titans, and then says that they won't hurt it at all. The Titan ignores Hange's words and tries to grab her, but Hange quickly dodges and cuts its nape. She then lands on the ground, while asking the Titan if their attack didn't hurt at all before it falls.

Back to Levi, as he approaches a group of Titans, he thinks to himself that they are all the same; the same ridiculous faces. He gets blood on his hands when he finishes a Titan off, causing him to take pause and immediately clean it up. Taking a short break, he joins Petra and the soldier he saved earlier. With the soldier's dying breath, he asks Levi if he has been useful. Encouraging him, he takes the soldier's hand and tells him he has done more than enough, which allows him to die in peace. Commander Erwin approaches them on a horse, informing them that they must retreat. When Levi questions why, Erwin informs him of the latest attack on the city and the movement of the Titans toward it. Worried that the wall may already be broken, they leave.

Back to the point when Eren was eaten by a Titan right in front of Armin, the mouth bites down, removing Eren's left arm. Now in the Titan's stomach, Eren is surrounded by the bodies of the dead and dying. In disbelief, he remembers all of his training and how he's changed these past five years. He begins to remember about his mom. Questioning why the Titans took everything from him, he again swears he will erase them from this world.

Suddenly, a left arm appears and forces its way out of the Titan's throat, exiting its mouth. The Titan collapses and Eren, in his Titan form, bursts out of its abdomen. As he leaves the corpse, he encounters his first Titan. Strangely, it reacts to it as it would to a human, going in for an attack. With almost no effort, Eren punches a hole through its head, straight through its weak spot. Seeing his new found power, he wants to kill more.

Apparently dreaming, Eren wakes up saying "I'll kill you". Noticing the situation, he sees that soldiers have him backed into a corner, while Mikasa and Armin try to defend him. Armin asks if he's himself again or not, then begs Eren to tell the soldiers what he knows. A couple of soldiers overhears his statement about killing and mistakenly believe he is referring to them. Eren begins to question himself why everyone is raising their weapon to them and glowering to him.

Inside the Wall Rose, Connie explains how they were able to refill their gas and escape from Trost to Ymir, Christa and the other soldiers. Christa asks about the rest of the soldiers that aren't there, and Connie answers with sad expression. Ymir questions Mikasa's whereabouts and Connie replies that he thinks Mikasa has come back late with Jean. She asks Jean if Mikasa was wounded, but Jean refuses to answer it, saying that he has sworn to keep it secret from the others, but believing that soon everyone will know it.

On top of the wall, Hannes is talking about how good is the new defense plan the technical crew made, but they still cannot let their guard down. When he looks at his comrade's face he asks what's wrong with him. His comrade says that he only worries about his friends that stayed in the vanguard. Hannes encourages him to stay focused on interception, but then his comrade asks about Eren, Mikasa and Armin because he heard they also remained in vanguard. He then apologizes for talking too much, but Hannes says that he believes in them.

Meanwhile, Eren is given a difficult situation. If he manages to say something deceitful or move even an inch, a cannon is ready to shoot him anytime. The officer questions him asking if he is a human or a Titan. Not understanding, Eren asks what he means. Losing patience, the officer states that there were numerous witnesses that saw him coming out of the Titan, which in effect, makes him the enemy. Not wanting to risk any more soldiers, an officer near him suggests that they kill him while he's still in human form.

Mikasa informs the surrounding soldiers that if they try to get close to them, she will demonstrate how good she is at what she does. The soldier in charge of the rear guard tells the officer that Mikasa is one of their best and it would be a great loss if she was killed. While Armin suggests fleeing, Eren tries to remember what has happened. He looks at his left arm, and he starts to realize that what he saw wasn't just a dream. When the officer asks again what he is, Eren knows that his answer affects his friends as well. Telling them he's human, the officer orders the cannons to fire on them. Mikasa grabs Eren and tells him and Armin that they are going away.

That is when Eren witnesses a key coming out from his clothes. Looking at it for awhile, he thinks back to a time with his father. His father hands him a key and tell him the importance of keeping it with him and explains that the injections will cause memory loss. He also reminds him of the basement, saying that although it would be a harsh journey, the "power" would be useful and he would find answers there. Time seems to slow down as one last phrase rings through his head, "If you wish to protect Mikasa and Armin, you must embrace this power and become its master". As the cannon fires, Eren bites down on his hand. An explosion seemingly happens around Eren and his friends. When the smoke clears, the onlookers are shocked to see the hollowed out torso of a Titan with Mikasa and Armin safe inside.