Hellsing Ultimate is an OVA which stays truer to the mangas plot. The first two episodes of the OVA are a retelling of the tv series up to the episode featuring the Valentine Brothers attack on Hellsing\'s HQ after this the OVA diverges keeping in touch with the manga. Millennium a group from Alucard\'s past emerges from the shadows Millennium was founded before the end of World War II, by \"Hitler\'s Special Order #666\" (an obvious reference to the mark of the beast in the Book of Revelation), as a means of researching and using supernatural phenomena for military purposes. In 1944, their grand project of creating a vampire army was foiled by a 14-year-old Walter C. Dornez and his accomplice, Alucard (who had apparently taken on the form of a young girl).
After this event, Millennium began to plan their escape. Some time after the end of the war in Europe, most of the members had left for South America, taking with them a battalion of 1,000 Waffen-SS volunteers. This was known as the \"Letztes Bataillon,\" translated in English as the \"Last Battalion,\" a secret weapon to be used in a future conflict. They also brought with them a massive amount of valuables taken from victims of the Holocaust, as well as an assortment of advanced weaponry, such as V-1 flying bombs, V-2 rockets and advanced Zeppelins. Now in 1999 they are back and intend to finish what they failed to do in 1944. Will Hellsing be able to defeat them for a second time and put an end to their schemes once and for all?