Released in 2004, Elfen Lied still holds up quite decently to this day. While its animation and sound quality are obviously subpar to the average modern anime, it makes it up by having really great scenery and a fantastic plot and lore. A Diclonious, a humanoid being with "vectors", invisible hands, and a desire to exterminate the human race; this is the main focus of Elfen Lied's plot. The story focuses on Kota, a college student who moves to a town he used to visit as a kid, in which his cousin lives, and on Lucy, a diclonious who escapes the facility she's being held in.
Elfen Lied gives us a story that has no filters whatsoever, dealing with every single piece of depravity and darkness that our world has to offer. Murder, rape, child abuse, inhuman experimentation, animal abuse and other extremely dark topics come together and bind to shape the characters and the world in a way that explains the events that take place through the 13 episodes of the anime. While a good chunk of the appeal of Elfen Lied revolves around gore and nudity, these only complement the plot and work as a way to allow it to develop the way it does. The diclonious are a mutant race which are basically genetically coded to exterminate humans, but they're not unlike humans, as they also have feelings, emotions and desires. However, humans are known for being judgmental, and throughout the events of Elfen Lied we see how diclonious are discriminated against, provoking their murderous instincts, which contrasts with their human condition.
The way Elfen Lied manages to be impactful is in the way its story is told. Its plot isn't rushed and the different aspects of its lore are explained gradually, as to not confuse the viewer. Our main character, Kota, lives through the trauma of his sister and father having died, while Lucy lives with the guilt of the things she has done to someone she loves. Kota and Lucy eventually meet, while Lucy develops a second personality after escaping the facility she was held captive in. As the story progresses, we get to know more about their past, and why they are who and how they are. The story then progressively introduces more characters, all of them with equally messed up backgrounds. Then, as everything moves forward, so do our characters, as Elfen Lied has a very good character development (for most characters, at least), as we see them change their ways of being and thinking at a coherent pace, unlike other animes which either rush it or delay it too much.
Elfen Lied's visuals are amazing, to be fair. The character design is quite good, with that of Lucy's (and her alter egos) having a huge meaning in the lore. The scenery and backgrounds still hold up very well to this day, with some real beauty in them. The gore is detailed and ludicrous, there's just a certain degree of satisfaction you get from watching the gory scenes throughout the anime (most of them, at least) due to how well they're made.
The voice acting is, for the most part, good, but the sound design tends to fall off a little bit, but that's probably because it's hard not to compare Elfen Lied to modern animes which a much greater production value. The soundtrack is one of Elfen Lied's strong points as well; while there aren't that many tracks in it, and a few of them are a bit overused (namely the main theme song), the atmosphere it helps create is great; the anime's atmosphere is thick and tense, it has a great power to transmit a sense of both melancholy and dread into the audience, fully enveloping them with the fucked up darkness the story isn't afraid to touch on. Very few animes manage to make someone feel as uneasy or emotionally impacted as this one.
The entirety of Elfen Lied also works greatly through its allegorical aspects; the story, lore, characters, imagery and else make a lot of reference to religion, to a point in which Elfen Lied can almost be interpreted as a metaphor for the Bible at times. The attention to detail throughout the whole show is amazing, although it's quite easy to miss when you don't pay attention. This results in the entire lore having great depth and an even greater impact than it already has.
Generally, I aim my reviews to those who've already watched an anime, as I tend to focus a lot on specific plot points, effectively spoiling the entire anime, however, I can't bring myself to do this with Elfen Lied, as I want this review to hopefully be read by someone who will be interested in watching the anime after reading it. If your heart can take this and your stomach can digest it, Elfen Lied is a must-watch.
