Off-duty Japan Self-Defense Forces (JSDF) officer and otaku Youji Itami is on his way to attend a doujin convention in Ginza, Tokyo when a mysterious portal in the shape of a large gate suddenly appears. From this gate, supernatural creatures and warriors clad in medieval armor emerge, charging through the city, killing and destroying everything in their path. With swift actions, Youji saves as many lives as he can while the rest of the JSDF direct their efforts toward stopping the invasion. Three months after the attack, Youji has been tasked with leading a special recon team, as part of a JSDF task force, that will be sent to the world beyond the gate—now being referred to as the Special Region. They must travel into this unknown world in order to learn more about what they are dealing with and attempt to befriend the locals in hopes of creating peaceful ties with the ruling empire. But if they fail, they face the consequence of participating in a devastating war that will engulf both sides of the gate.

The eccentric, self-proclaimed mad scientist Rintarou Okabe has become a shell of his former self. Depressed and traumatized after failing to rescue his friend Makise Kurisu, he has decided to forsake his mad scientist alter ego and live as an ordinary college student. Surrounded by friends who know little of his time travel experiences, Okabe spends his days trying to forget the horrors of his adventures alone. While working as a receptionist at a college technology forum, Okabe meets the short, spunky Maho Hiyajo, who later turns out to be the interpreter at the forum's presentation, conducted by Professor Alexis Leskinen. In front of a stunned crowd, Alexis and Maho unveil Amadeus—a revolutionary AI capable of storing a person's memories and creating a perfect simulation of that person complete with their personality and quirks. Meeting with Maho and Alexis after the presentation, Okabe learns that the two were Kurisu's colleagues in university, and that they have simulated her in Amadeus. Hired by Alexis to research the simulation's behavior, Okabe is given the chance to interact with the shadow of a long-lost dear friend. Dangerously tangled in the past, Okabe must face the harsh reality and carefully maneuver around the disastrous consequences that come with disturbing the natural flow of time.

After saving the Kingdom of Liones from the 10 Commandments, Meliodas and the Seven Deadly Sins are enjoying their time off. However, things aren't as peaceful as they seem, as the Sins are put through various trials to become strong enough to defeat the 10 Commandments and to overcome their past trauma. With help from past figures, the Sins are tasked with defeating the 10 Commandments and putting an end to their evil plans that began ten thousand years ago. The Sins begin to uncover the truth about each other, as well as those who stood before them. With this knowledge in hand, the battle against the 10 Commandments has only just begun. Nanatsu no Taizai: Kamigami no Gekirin continues to follow the Seven Deadly Sins and those that they meet on their journey. Through their adventures, they realize that their actions have had greater consequences on the present than they could have ever expected.

According to the Republic of San Magnolia, their ongoing war against the Giadian Empire has no casualties—however, that is mere propaganda. While the silver-haired Alba of the Republic's eighty-five sectors live safely behind protective walls, those of different appearances are interned in a secret eighty-sixth faction. Known within the military as the Eighty-Six, they are forced to fight against the Empire's autonomous Legion under the command of the Republican Handlers. Vladilena Milizé is assigned to the Spearhead squadron to replace their previous Handler. Shunned by her peers for being a fellow Eighty-Six supporter, she continues to fight against their inhumane discrimination. Shinei Nouzen is the captain of the Spearhead squadron. Infamous for being the sole survivor of every squadron he's been in, he insists on shouldering the names and wishes of his fallen comrades. When the fates of these young souls from two different worlds collide, will it ignite the spark that lights their path to salvation, or will they burn themselves in the flames of despair?