Watch World Trigger 3rd Season Online

At the Border Defense Agency's headquarters, the B-Rank Wars are underway as each team fights intensely to secure a spot in the upcoming Away Mission. Though Osamu Mikumo and the rest of Tamakoma-2 have pulled through thus far, the final rounds will require them to push far beyond the limits of their current abilities. Taking in a talented new member, the squad begins to train and develop new strategies, but, amid these efforts, the team is shaken by a heated dispute—one that could jeopardize their ticket to the Neighbor's dimension.

After successfully holding off the invasion by Aftokrator, the Border Defense Agency prepares an away mission into the Neighbor's dimension. However, like in previous scouting expeditions, only A-rank teams are certain to secure a spot. As the B-rank wars continue, Osamu Mikumo and the rest of Tamakoma-2 quickly fight to the top in an attempt to obtain a promotion before the operation begins. Meanwhile, a new Neighbor ship approaches Border Headquarters. Noticing that the attackers are targeting the Border Expedition Ship, forces are hastily sent to combat them. However, with fewer squads available due to the proceeding rank wars, the organization is sent into disarray. This latest offensive from the Neighbors shrouds the fate of the all-important expedition ship in uncertainty.

When a gate to another world suddenly opens on Earth, Mikado City is invaded by strange creatures known as "Neighbors," malicious beings impervious to traditional weaponry. In response to their arrival, an organization called the Border Defense Agency has been established to combat the Neighbor menace through special weapons called "Triggers." Even though several years have passed after the gate first opened, Neighbors are still a threat and members of Border remain on guard to ensure the safety of the planet. Despite this delicate situation, members-in-training, such as Osamu Mikumo, are not permitted to use their Triggers outside of headquarters. But when the mysterious new student in his class is dragged into a forbidden area by bullies, they are attacked by Neighbors, and Osamu has no choice but to do what he believes is right. Much to his surprise, however, the transfer student Yuuma Kuga makes short work of the aliens, revealing that he is a humanoid Neighbor in disguise. [Written by MAL Rewrite]