Kouta Hirano both wrote and illustrated the Japanese manga series Hellsing. In 1997, Youn King Ours premiered the series and it ran until September 2008. There were a total of ten volumes that Shonen Gahosha collected and published. Hirano began to work on a prequel in 2001 called Hellsing: The Dawn.
An anime series was adapted from the manga, but was greatly different. The reason is that the director, Umanosuke Iida, used another screenplay for the series that was written by Chiaki Konaka. The characters remained the same, but the plot changed drastically. The series ran on Fuji Television from October 2001 to January 2002. In 2006, an OVA that was adapted from more closely from the manga, aired until December of 2012. There were a total of ten episodes.
The plot follows the Hellsing organization. It was originally led by Van Helsing himself. The group finds and destroys supernatural and undead beings. Sir Integra leads the organization at the moment. It is said that she is protected by an old family bodyguard, Alucard, who is a vampire himself. He is the original vampire and therefore the strongest. He swore his loyalty to the family years ago when Van Helsing defeated him. With others, such as Seres Victoria, the group is in search of a large neo-Nazi group known as Millennium. They share another enemy known as the Vatican section XIII. The battle takes place in London.
Why I chose this anime: I was never a fan of the Hellsing manga, but I loved the TV series. Though the story is somewhat similar, it had a drastically different ending.