For a rare occasion, the members of Libra have come out of the shadows to dine with an important guest: a royal next in line for the crown of his country. To show their visitor the finest that Hellsalem's Lot has to offer, the group decides to dine at Molzzogazza, the cream of the crop as far as restaurants go in the city. As the success of this dinner may prove to be beneficial to Libra, Steven A. Starphase mounts the pressure on the team to be on its best behavior and avoid screw-ups. However, Steven has made one oversight. Molzzogazza, famous for its cuisine's indescribable and transcendent flavors, serves food so good that most people lose their minds eating it. Though the ragtag team may do their best to be cordial, the food is sure to unwind their composure, threatening the success of the dinner and leaving them unaware of an oncoming threat to the restaurant.

Whenever he is not getting pummeled in the karate club after school, high schooler Kenichi Shirahama can be found with his head buried in one of the many self-help books he carries with him every day. One day, on the way to school, Kenichi accidentally frightens the new student in his class, leading her to throw him down onto the ground. After apologizing for her violent reflexes, she introduces herself as Miu Furinji and asks Kenichi to be her friend. Later that day, after karate club practice, Kenichi is given an ultimatum by one of the other club members: they will fight next week and the loser has to quit the club permanently. While lamenting his imminent defeat in the upcoming fight, Kenichi witnesses Miu fend off three thugs easily. Fed up with being perpetually bullied by those more powerful than him, he asks Miu for tips on how to become a better fighter. She directs Kenichi to her grandfather's dojo, Ryouzanpaku, where several skilled—albeit strange—masters of extreme martial arts have gathered to hone their abilities. Miu promises that Kenichi will become significantly stronger, but only if he manages to stay alive. With those ominous words looming in his mind and the appearance of a criminal martial arts gang known as Ragnarok threatening the safety of those around him, Kenichi takes the first step on his journey to become a world-class fighter and a defender of the defenseless.

Yoshimura Sumimura comes from a long line of Kekkaishi, individuals who have supernatural abilities and are able to destroy evil creatures called Ayakashi that venture into the human realm from time to time. The Ayakashi are demons that look to feast on the power emanating from the land of Karasumori, which also happens to be where Yoshimura's high school is located. Now, Yoshimura must fight to protect his beloved school and hometown. Although, if it were up to him, he would rather be baking cakes than fighting off the ugly characters that show up at night. Thankfully, Yoshimura isn't the only one helping to keep the baddies at bay. His childhood friend and neighbor, Tokine Yukimura, joins him in this righteous battle. Despite the fact that they are from rival clans, these two make a fantastic team. And teamwork is something vital to fighting the evil that is closing in, as the Ayakashi attack in waves, looking to claim the land as their own, and a shadowy organization looks on, ready to pounce when the time is right...

Supersonic monkeys, vampires, talking fishmen, and all sorts of different supernatural monsters living alongside humans—this has been part of daily life in Hellsalem's Lot, formerly known as New York City, for some time now. When a gateway between Earth and the Beyond opened three years ago, New Yorkers and creatures from the other dimension alike were trapped in an impenetrable bubble and were forced to live together. Libra is a secret organization composed of eccentrics and superhumans, tasked with keeping order in the city and making sure that chaos doesn't spread to the rest of the world. Pursuing photography as a hobby, Leonardo Watch is living a normal life with his parents and sister. But when he obtains the All-seeing Eyes of the Gods at the expense of his sister's eyesight, he goes to Hellsalem's Lot in order to help her by finding answers about the mysterious powers he received. He soon runs into Libra, and when Leo unexpectedly joins their ranks, he gets more than what he bargained for. Kekkai Sensen follows Leo's misadventures in the strangest place on Earth with his equally strange comrades—as the ordinary boy unwittingly sees his life take a turn for the extraordinary.