Kyoto Animation has a strong track record for producing top-notch TV anime, and though they are probably best known for series such as Haruhi and K-ON!, Clannad stands out to me as the brightest gem in their catalog of fantastic shows. Clannad is the true culmination of not only moe harem comedies, but also of slice-of-life family dramas. This series (almost) achieves perfection on practically all fronts, and its ~47 episode length (depending on how you count extras and summaries and OVAs) is utilized to the fullest, making it one of the few long anime (i.e. anything more than two seasons long, by my standards) I would ever recommend investing the time in. And MAN is it worth investing time in!
Clannad is divided into two series, and they're very different, so let's begin with the first, simply titled Clannad. This first part of the story is mostly your typical high school comedy fare (mostly...), and it's legitimately hilarious. Even if this was all Clannad was, it would probably still be worth a 5 star rating. The plot at this point follows the standard dating-sim-adaptation formula of giving each major female character a story arc that lasts a few episodes, exploring each character's history and resolving various personal conflicts, so as I hinted at above, there is a fair amount of character drama. However, the memorable moments here are the funny ones, like Tomoyo's 1000-kick combos on Sunohara, Kotomi's killer violin playing, and Fuuko's gullibility with regard to Okazaki's supposed sex change. The writing is always clever, and the characters are great both in their own right and in their interactions.
But the second series, Clannad After Story, kicks it up a notch. Comedy still persists, just as there was drama in the first series, but the focus shifts onto the trials and tribulations of Okazaki and Nagisa's life after high school. How does a slacker like Okazaki deal with finding a job and moving out on his own? Can Nagisa deal with repeating her senior year again due to her recurring illnesses? What about starting a family? Can they deal with an alcoholic parent being thrown in jail? Real life hits these characters hard, and following their struggles over several years really builds an emotional connection to the story within the viewer. At times, this can be one of the most heart-wrenching tales ever spun in the anime medium, and it's all because of the way the story is presented. You see these characters at their best and their worst, and the length of the series allows for the characters to be fully fleshed out in order to develop personal attachment in the viewer, and the comedic first half makes the dramatic payoff in After Story that much more worthwhile. The shift from low-stakes to high-stakes storytelling is a metamorphosis showcasing the range that developers Key and Kyoto Animation are capable of.
Really the only negative thing I can say about Clannad is that the ending is a total cop-out. I try my best to forget the last ~half episode or so because without that it would be one of my favorite endings, but to ignore that would undercut the entire series' framing device, so I guess you kinda have to take it for what it is. But at the same time, the inclusion of that ending undercuts the very drama that I adore this series for. You can't really win..... But honestly, I'm arguing over literally ~1% of the show's total run time, and in every other respect this is one of the most satisfying viewing experiences I have ever had. This is the definition of a must-watch series as far as I'm concerned, even if that sounds a little crazy to some.
--The Anime Hipster