Shingeki no Kyojin (進撃の巨人 – “Advancing Giants”) was originally a Japanese manga series written and illustrated by Hajime Isayama. It was initially serialized on the 9th of September 2009 in Kodansha’s Bessatsu Shounen Magazine. It was later adapted as an anime series, produced by Wit Studio and Production I.G. with its first episode airing on the 6th of April 2013 and its last episode airing on the 28th of September, 2013. It has become a commercial success having 40 million volumes printed as of July 2014.
A live action film adaptation is also in production.
"Several hundred years ago, humans were nearly annihilated by Titans. These so-called Titans are usually several stories tall, and do not seem to show any sign of intellect. And the only thing that seems to motivate them to wander is to devour humans and what is worse is that they only do so for pleasure rather than as a need to satisfy hunger.
The last bastion of humankind built three concentric massive walls surrounding the city within, high and strong enough to keep the murderous Titans from pressing on their mad rampage. Many years have passed and the wall continues to protect the people within it until one day, a colossal Titan the likes never seen before appeared before the wall and destroyed it, allowing the other Titans to invade the city within.
Amidst the chaos, a young boy named Eren Jaegar and his adoptive sister Mikasa Ackerman, witnessed in horror as their mother was gruesomely devoured by one of the Titans. After managing to escape with their childhood friend Armin Arlert, Eren vowed that he will kill every existing Titan and take revenge for mankind. With this in mind, the three decided to join the military in hopes that it will serve as a stepping stone in combating the Titan menace."
Similar Series: Shingeki no Kyojin has a dark and realistic atmosphere that can be compared to the anime Claymore.