I've watched many anime series since I was about 12 years old, most of which are fantasy, adventure combined with good character development and visuals. Now 21, most of the series found in my DVD collection I've loved at first glance of the cover/synopsis and never looked back. The same goes for Elfen Lied.
The story centres around a mutant race known as "diclionius", who are mainly pink haired, female, have noticable horns growing from their heads and have psychic abilities from their invisible-to-the-naked-eye hands known as "vectors". The main focus from this race is Lucy, a sadistic woman bent on destroying the human race as she breaks free from a research facilty. After attempting to escape she washes ashore in a nearby town where two innocent college students find her...
After watching the first 2 minutes from the pilot episode, its easy to make the assumption that it's made for fanservice only. The opening titles have pictures of naked girls and Lucy, as she goes on a killing spree in the first episode, walks around naked, however after the pilot episode its goes into so much more depth than most 'fan service' based material.
Though the series is dominated by violence and sexual content (nothing porn related, just lots of nakedness), this is forgiven since the series takes a very dark tone. The violence and sexual content is meant to stress the dark side of humanity and empathise the trauma the character has suffered, not just to please its audience.
The music is beautiful, not just the opening and ending themes but the music score is wonderfully composed and fits the anime well. The art is some of the best I've seen, and though the series takes small elements from other series - as a whole it's original and is considered one of my favourites.
The biggest flaw I experienced from the series is the background story; lots of questions were raised and were not answered, many characters "flashbacks" are set at least 8 years before the anime series begins, yet offers no input in between the gaps. For example many 'Lucy' flashbacks took place when she was 10 years old, in the series she's 18 and you never find out how she became captured by the research facility and the series does not go into too much depth about the "diclonius" race. Though some questions are answered in a special OVA episode, its not avaliable officially outside of Japan. This factor to me though only made me want to watch the series again, and create a great desire to read the manga, which is yet to be translated into English but have discovered that it goes into much more depth that the anime fails too.
If you can watch anime in Japanese with Subtitles, I recommened you do so. The English dud voices are not the worst I've heard, but after the first 2 disks they become tiresome. My main annoyance it towards the females voices, with an exception of a few, most of them have high pitched breathy voices. They sound like they are all done by the same actress. What's worst is that the characters with those voices happen to be the most whinney/child-like of the cast - not a good combination!
DVD Extras wise, there isn't much to offer; on all disks you'll find a clean opening and closing, character artwork, production artwork, DVD credits and ADV previews - most of which are the same consistantly on all 4 disks.
Despite it's flaws I highly recommend this series to all anime fans, it offers a fresh insight on the genre and is worth adding to any DVD self. If you can't stand the sight of blood and body parts being ripped apart, this series certainly isn't for you. The same goes for those who want an anime series to answer all the questions it raises, you'll only get disappointment. However if you can overlook this and enjoy it for what it is, you'll find this quite enjoyable.
Please note that I own the four volumes separately and not the box set above, but I have read elsewhere that there are no differences between them.