Robin Sena arrives in Japan to replace a fallen member of the STN-J. Engrossed in a witch hunt, the members of the team are unaware that this quiet 15-year-old is the new Hunter and brush her off. When they finally corner the Witch will they come to appreciate Robin's power?

The STN-J is called in by the local police when a dried corpse is found. When Robin finds a dead insect on the body the team goes on a hunt for a Witch who can control insects. They find that there were two previous victims found in the same condition. The cases point to a similar rash of deaths leading back hundreds of years. Apparently, all the dead are Witches. Is the STN-J dealing with an immortal who feeds on Witches?

When a suspected thief's wrecked car is pulled from the harbor, the STN-J suspect there is more going on then a mere accident. When the go to question the suspect, however, he flees in his car, crushing Karasuma's vehicle with a powerful blow in the process. But, was it the thief doing the crushing or a more sinister force?

When two bodies are found apparently burned from the inside out, attention is drawn to Robin; whoever did this has the same power she has. A girl named Aki Yoshioka is the best suspect, but when the STN-J investigates they only find a pile of sand and a confession to killing three people on Aki's computer. Is the team chasing a ghost?

As part of an STN-J a sting, Dogima and Robin take jobs as waitresses in Harry's bar. The man they're hunting was once betrayed to the STN-J by his own father, the owner of Harry's. As they wait for the prodigal son to return, the STN-J begin to realize that they're not the only ones after Yutaka Kobari.

After the most recent attacks, the Team keeps Robin under careful guard at the STN-J. The only one absent is Amon, who can't be reached. As they analyze the odd shell castings left from the attack at Robin's apartment, they find that only three people could have fired the Witch bullet at Robin. Unfortunately, the prime suspect has been dead for years. With growing uneasiness, they realize the only other person that could do this is someone very close to them all.

Robin and Amon finally confront Zaizen and learn the truth about Robin's existence. To Zaizen's surprise, instead of being traumatized, Robin is instead strengthened with resolve. Now Robin and Amon must stop Zainzen's final solution for the sake of both Witches and Humans alike.