In the subterranean gloom of the Underground, Levi and his companions, Furlan and Isabel, are notorious for their skill with stolen Vertical Maneuvering Equipment (VME). Their prowess catches the attention of Nicholas Lobov, a corrupt official who offers them citizenship in the surface world and a hefty reward in exchange for a dangerous mission: assassinate Erwin Smith, a rising commander in the Survey Corps, and retrieve a certain document.
The Survey Corps soon conducts a raid to capture the group. During a high-stakes chase through the cramped tunnels, Levi displays combat skills that rival even the best soldiers. Despite their agility, they are eventually cornered by Erwin Smith. Rather than arresting them, Erwin offers Levi a choice: join the Survey Corps and use his talents for humanity’s survival, or face prosecution in the Underground. Recognizing an opportunity to fulfill his mission, Levi accepts, marking the beginning of his journey from a street thug to humanity's strongest soldier. Shingeki no Kyojin: Kuinaki Sentaku Episode 1