First  OVA series: Sanctuary
Meiou Hades Juni Kyuu Hen (12 Temples)

These 13 episodes tell the events of the last manga series, first part.
Athena has born on the Earth to fight against Hades, King of the Underworld; the previous battles against Ares, Asgard and Poseidon were only secondary skirmishes. After 243 years from the last Holy War, Hades has awaken, too, and has given a new life to the Silver and Gold Saints who died during the battle of the 12 Temples.
Saga, Death Mask, Shura, Camus, Aphrodite and Sion (the old Pope) have 12 hours to pass through the 12 Temples and cut off Athena's head. They have to fight against the Gold Saints still loyal to Athena, such as Mur and Libra, who have always been peaceful since now, and Kanon, who joined Athena's army after his betrayal. Also the Bronze Saints join the war to help the Gold Saints, but have a secondary role, because Athena doesn't want them to risk thier lives.
After many battles, that involve also the Spectres (the real Hades's Saints), it comes out that Sion and the others (except for Death Mask and Aphrodite) have never betrayedn Athena: as a matter of facts, they have simulated to be evil only to reach Athena and tell her about the existence of her Holy Cloth.
At the end, Athena decides to suicide to reach Hades in the Underworld and beat him forever.

EPISODES LIST CHAPTER SANCTUARY:

1. Aratanaru seisen no hajimari 
2. Dokoku no sannin 
3. Ugomeku mono no kage 
4. Hanshin no shokuzai
5. Karisome no saikai
6. Inishie no toshi
7. Kuroki koromo no mure
8. Shunjun no toki
9. Kyouji no hate
10. Kiniro no gekitotsu
11. Shinkan no Sanctuary
12. Athena no Kurosu
13. Ketsui no asa

Second OVA series: INFERNO
Meiou Hades Mekai Hen

The Knights of Zodiac gain eighth sense and can enter underworld without loosing their lives, in order to bring to Athena her sacred Cloth, necessary for the holy war against Hades.
The Gold Saints are dead or lost, so the Bronze Saints have to pass by themselves various Dante's prisons, defeat their guardians Spectres and reach Giudecca, Hades's palace. To help Bronze Saints there are Orfeo, former legendary Silver Saint, Kanon and Shaka, survived because he has eighth sense.
But a sad reality waits for them: the reincarnation of the god of underworld is just Andromeda himself!
At the end, Hades's soul leaves Shun's boby, but kidnaps Athena and takes her to Elysium. To reach Athena, the Bronze Saints have to destroy the Wailing Wall, but they succeed only thanks to the sacrifice of the Gold Saints.

INFERNO FIRST PART - ZENSHO:

1. Watare! Acheron no kawa!
2. Shizuka-naru hotei
3. Densetsu no Saint Orfeo
4. Orfeo kanashiki chinkonka
5. Hades! Kyogaku no hyoi
6. Gekito! Giudecca e no michi

7. Shinbatsu! Greatest Eclypse
8. Ikki! Dokoku no ken
9. Megami! So no inochi o kakete
10. Zetsubo! Nageki no kabe
11. Shoketsu! Gold Cloth
12. Saraba! Ogon no Saint

Third OVA series: ELISYON
Meiou Hades Elysion

Thanks to their Clothes regenerated by Athena's blood, the Bronze Saints upgrade to Divine Knights and reach Elysium, the Heaven of Gods. After defeating Thanatos and Hypnos, they face the true body of Hades. Seiya is badly hurt, but Athena and the other Saints kill Hades forever.

EPISODE LIST ELYSION:

1. Elysion e no Michi
2. Shi to nemuri no kamigami
3. Ougon no engun
4. Densetsu no God Cloth
5. Shinwa yori no kakusei
6. Hikaru afureru sekai e