Hellsing follows the secret British organization Hellsing, led by Sir Integra Hellsing, which fights against vampires and other supernatural creatures. Its most powerful weapon is Alucard, an immortal and fearsome vampire who works for the organization. The plot intensifies when the Nazi group Millennium launches an attack with artificial vampires in London, unleashing a brutal war. Readers enjoy the series for its violent and stylized action, dark and gothic atmosphere, and the charisma of its characters, especially the antihero Alucard, whose monstrous nature and conflicted loyalty create constant tension.