In the aftermath events of GARO: Chapter of the Black Wolf, Kouga Saejima sets out to the northern district upon reassignment. While hunting down Horrors, a young priestess named Rin informs Kouga that she has been sent by Priest Amon to save a presumed dead friend in the Makai realm within Kantai, Jabi. Kouga teams up with Rin in a quest to save Jabi as they are hindered by supernatural and Makai forces alike. Meanwhile somewhere in Japan the dark Horror Lord Legules was resurrected and plots a means to alter a supernatural event called White Night within Kantai to plunge the world into darkness with his "family."
- Ryōsei Konishi as Kouga Saejima/Golden Fang Knight GARO
- Mika Hijii as Kaoru Mitsuki
- Ray Fujita as Rei Suzumura/Silver Fang Knight ZERO
- Yukijirou Hotaru as Gonza
- Hironobu Kageyama as Zaruba (voice)
- Ai Orikasa as Silva (voice)
- Ogata Kenichi as Garuba (voice)
- Mark Musashi as Kodama
- Yasue Sato as Jabi the Makai Priest
- Shouma Yamamoto as Tsubasa Yamagatana/White Night Knight DAN
- Hiroyuki Watanabe as Taiga Saejima/Golden Fang Knight GARO
The story takes place after the events of Chapter of the Black Wolf. Young Makai Priestess trainee, Rin Yamagatana, was visited by the spirit of Amon. Having urgency to find Kouga, Amon had Rin find Kouga to relay his message. However, he not an easy man to find; she decided to have Kouga find her instead. By smearing a small amount of Horror's blood on her bag, she made a deadly gamble that Kouga would appear before the Horror gets to her first.
While traveling through a commercial building, a young beautiful woman is being pulled away by a male thug, assuring her all he wants to do is "talk" to her; unknown to him, he was just lured by the Horror Eruzu. Rin appeared and revealed her brush to the confused thug. It was then that Kouga appeared and warned the thug to run. Still confused as to what's happening, Kouga suggested the thug to run and chase after "human girls." Insulted, he tries to attack Kouga while still holding onto the girl; it was the Eruzu began to reveal herself.
While attempting to hit Kouga, he was still tugging the woman when she suddenly revealed surprising strength. The thug got spooked and both he and Rin stood next to Kouga for safety. Kouga used his lighter to emit the green Madou Flame to reveal she's a Horror. Eruzu grew an extra pair of arms out of her eye sockets and took the lighter away. Freaked out, the thug runs for his life while Kouga protects him from being webbed down; Eruzu turns her attention to Rin.
Kouga attempts to intervene, but Eruzu spits out a large webbing that gets his right arm and sword stuck. While attempting to break free, Eruzu tries to hunt and devour Rin. Kouga frees himself and protects Rin from harm. Tired of Kouga's interference, Eruzu transforms into her complete Horror form and the two take the battle to a parking lot.
At the parking lot, Eruzu manages to shoot a webbing that pushes Kouga up to the side of the building and bonded him to the building. While stuck, Eruzu webs a car and flings it in attempts to crush Kouga. The car crashed into the side of the building where Kouga was tied down, but he managed to evade the attack and breaks free. Kouga then kicks the car loose to fly towards Eruzu mid-air for a final assault.
Eruzu fires a volley of projectiles and Kouga uses his scabbard to block the incoming attacks, but the car caught on fire. As the car burns, Kouga transforms into Garo and utilizes his falling speed make a charging slash attack to cut down Eruzu in half; it was not the end. The two chopped ends regenerated and now there are two Eruzus to contend with. Zaruba warns Kouga that Eruzu can only be destroyed by fire; cutting the Horrow will cause it to multiply. Garo pierced through Eruzu's head, where it contained his lighter and causing the Horror to burn. Taking advantage of his flaming sword, he cuts down the other half and ends the the terror of Eruzu.
After defeating Eruzu, Kouga retracts his armor. It was then that Zaruba faintly detects Horror's blood. Kouga quickly exposes Rin's use of Horror's blood and her Mahoui, revealing she's a trainee priestess of Kantai. Irritated at what Rin had done, he commands her to return to Kantai immediately; she refused. Rin angrily told Kouga that she had searched for him for many days and has a message from Priest Amon; Kouga was not amused and told her not to lie as Amon is dead and walks off. Rin defiantly exclaims that she's not lying as Amon revealed himself to her and mentioned their unfinished game of Bar-Chess as proof. Surprised of Rin knowing the private knowledge, Kouga started to take her seriously. Rin mentioned she was hungry and Kouga decided to take her
Kouga decided to take Rin back to the Saezima Estate to sort things out. Gonza treated Rin with pudding (something she never tried, but quickly fell in love with). Because Zaruba lost his memories, he asked about Amon (his creator) since he doesn't know him. Gonza and Kouga fills in Zaruba that Amon is a high-class priest and that Amon created Zaruba for Taiga Saezima before Kouga.
Refocusing on the matter at hand, Kouga asked Rin is she able to summon Amon. Rin confidently said that she brought all the necessary materials to perform a spiritual summon ceremony, but both Kouga and Gonza had their doubts. Eager to prove her competency, she tried a simple spell that backfired and it left a burned streak across the moonscape painting that Kaoru left for Kouga (it is very precious memento of their relationship). Rin attempted to try again, but Kouga was too angry at this point to be patient and took away her brush. However, Rin used a return spell and the brush forcefully pulled free and flew back into Rin's hand. She exclaimed that her brush is precious to her; Kouga had enough of her and walked off. Rin didn't think he had to be that angry, but Gonza corrected her and told her actions was serious.
In between this time, a couple just kidnapped and killed a person to inherit his (or her) money. While attempting to bury and hide the body in a secluded area, the corpse's blood leaked into the soil and dark energies began to stir. An ancient and powerful Horror, Legules, was drawn to the body and possessed the corpse. Through the corpse, Legules had awakened and he killed the woman. He then grabs the man and offers him a chance to live if he agrees to serve him (as an advanced scout); he agrees and Legules used his dark powers to transform him into Aomushi.
Back in Kouga's home, Rin just completed the summoning ceremony and calls forth Amon. Eager to test Kouga's reflexes, Amon attacks, but Kouga easily blocks it. Amon apologies for putting up a poor attack as his skills have dulled in the afterlife. Amon asked aobut Zaruba's well being, but Zaruba rudely said he doesn't remember him; Amon laughed and was fine with it. Amon then greeted Gonza, but pleasantries was short as the ceremony had a limited time. Amon got to the heart of his reason why he must speak to Kouga: Amon wants Kouga to rescue Jabi.
Jabi was thought to have died when Kodama launched a surprised attack that "killed" her, however, she's trapped in the spiritual realm. Jabi somehow survived the attack and is trapped within the Makai Beast, Miki, inside the Makai Forest. Trapped and in slumber, Miki somehow took hold of Jabi and evaded death, however, she won't awaken for another 200 years; Amon wants to take advantage of their strong bond to help awaken Jabi and have her return to the mortal realm. Kouga has his doubts, but Amon demonstrates how a spirit would look when one has lost their body and reaffirms that Jabi is alive and not a phantasm. Unfortunately, the ceremony had run its course, Amon welcomes the day they could continue their Bar Chess game, but hope it wouldn't be too soon and bids farewell. Kouga bows to Amon out of respect and thanked Rin to let him see Amon once more.
While Legules converts Horrors into his minions as he makes his way to Kantai. In another district, Rei encounters his first Karakuri and kills him as ZERO. In the aftermath he was assigned to Kantai to assist the Makai ritual of White Night to ensure nothing goes wrong. Kouga and the reluctant Rin enters Kantai to enter the Makai realm portal. As he entered Kouga was involved in an altercation between Tsubasa and his two disciples.
Tsubasa, Rin's older brother and a Makai Knight himself, was critical of Kouga's intentions and scolds his little sister Rin for getting involved in the matter, but Priestess Garai permitted entrance. As Kouga enters the Makai realm to save Jabi from the Makai beast, Rin must keep the portal open or Kouga will be lost forever. Meanwhile Tsubasa's disciples are attacked by Karakuris and were outmatched when Rei comes to save them. Tsubasa appears as well and takes up the form of DAN Knight of White Night to dispose of the remaining threat.
As Kouga defeats the illusions the Makai beast has thrown, Kouga faces the beasts' ultimate form and forces Kouga to transform into GARO, riding in with Gouten. Kouga eventually awakens Jabi from her slumber within the beast and Kouga summons GARO-ZEN-BA-KEN to slay the Makai beast and spirits Jabi back to the living, where Rin has kept the pathway open despite how frightening the situation was.
After Jabi has been resurrected, she trains Rin in her Makai magic skills. Priestess Garai reflects her memories over the Saejima family happily together before the couple's death and orphaning Kouga. Kouga receives orders of Legules and prepares for a counter-offensive with everyone. Priestess Garai explains that the White Night ritual is meant to keep the world whole by shooting the Phosphorus Arrow into the eclipse portal, but if the process was stained with innocent blood then the ritual will be a dark one that would revive Legules' legion.
Tsubasa wasn't pleased to know Jabi was brought back to life, claiming her to be undead. Jabi forces Tsubasa to feel her breast and breath to make him understand she's very much alive. After that argument was settled, they went to examine the Phosphorus Arrow in preparation for the White Night ritual that Legules has come to ruin. Jabi discovers the arrow's power has diminished and needs to be replenished. In between that time Rei, Kouga, and Tsubasa guards Kantai until the ritual starts. During nightfall Legules attacked, but failed. Unknown to the group, he left part of himself inside Goruba (Tsubasa's sentient bracelet) and patiently waited for his chance to strike.
The attack left Rin injured with dark energies flowing within her. Jabi opted to use a risky purification technique to save her, the process worked. After Tsubasa made his mends with Jabi and Rin, Legules appeared and stolen the Phosphorus Arrow along with kidnapping Rin. The group entered Naraku Forrest to save Rin and prevent the Phosphorus Arrow be tainted with innocent blood. As everyone fought their way in, Kouga faced Legules with the assistance of Jabi. The duo was losing, and to make matters worse, Legules taken a powerful beast Horror form. Kouga transformed into GARO and was caught in Legules attack when Kouga used the Phosphorus Arrow to purify his body and taken a new powerful form of GARO. The Phosphorus Arrow transformed into a spear and GARO thrust the arrow to kill Legules, completing the White Night ritual at the same time. With Legules's death,his minions were gone and Kantai was restored to peace. In the aftermath, Jabi stays in Kantai to look after Rin and Rei heads back to his district post as Kouga returns home to find Kaoru waiting for him in the yard after restoring the damaged painting.