For centuries, vampires have lurked in the shadows of England's streets. The Hellsing Organization, currently led by Integra Hellsing, has spent centuries fighting these monsters and keeping their existence a secret from the world. Alucard is a vampire sworn to serve Integra and follow Hellsing under her rule; Seras is a fledgling vampire subservient to Alucard, learning about vampire ways while struggling with her own lost mortality. Together they keep England safe from blood-drinking monsters, until a new breed of pseudo-vampire, the Freak, begins attacking people for fun and not to feed. Where are these Freaks coming from and what will Hellsing sacrifice to stop them?
Born beneath the gallows tree from which his dead mother hung, Guts has always existed on the boundary between life and death. After enduring a terrible childhood, he spends his adulthood in brutal combat, pitting his strength against others in order to build his own. Life is simple enough for Guts until he meets Griffith, the inspirational, ambitious, and beautiful leader of the mercenaries, the Band of the Hawk. When Guts loses to Griffith in a duel, he is forced to join the Band of the Hawk, and, despite himself, finds a sense of camaraderie and belonging amongst them. However, as Griffith leads his soldiers from victory to victory, the bloody wars and underhanded politics reveal a side to him that nobody quite expected. Very soon, what seems like a straightforward march for conquest becomes a harrowing struggle for humanity and life itself. Can Guts, a simple warrior, defend those who have come to mean the most to him, all the while struggling not to lose to the darkness he has carried with him his entire life?
In a land overrun by yoma - monsters that feed upon human innards and take on the appearance and memories of their victims - humans are little more than cattle awaiting slaughter. The only opposition to the yoma is The Organization, a group led by a council of mysterious men who send out their all-female warriors (known as claymores) to do their bidding. However, The Organization is not charitable; a town must pay an exorbitant fee for their services. Likewise, many of the claymores care little for those who they protect. Clare, the lowest ranked claymore, lives only so that she may one day avenge her mentor.
Fight creatures of the night in these dark times is not as easy as one might think. So how do you get rid of what you can't control? Easy, you get one of those creatures of the night to fight for you. And that is how both organizations fight, but is there more things going on than just fighting against the creatures of the night?