Code Geass is, at its heart, a story about two best friends on opposite sides of a war with differing ideas and ideologies working towards the same ultimate goal: the noble prince exiled to Japan who wishes revenge for the death of his mother and abandonment of his sister, and the son of Japan's last Prime Minister hoping to change the system from within.
Seven years before the events of the first season, Japan is invaded by the Holy Britannian Empire for control over 70% of the worlds sakuradite. This invasion was expedited by the invention of new combat "Knightmare Frames", a mecha that easily outclassed Japan's military defense systems.
Upon discovering the mysterious C.C and gaining the power of Geass, Lelouch Lamperouge sets his plans in motion buy killing his cousin Clovis and establishing the Black Knights, a terrorist group whose aim is to liberate Japan (now called Area 11), all for the sake of creating a world in which his sister can live peacefully.
"What do you do when there is an evil you cannot defeat by just means? Do you stain your hands with evil to destroy evil, or do you remain steadfastly just and righteous even if it means surrendering to evil?[...] In my case, I commit evil in order to destroy the greater evil!"
Lelouch is one of the most engaging characters in this anime and, in my opinion, anime as whole. As the main character he is just a delight to watch. His charisma just flows and you cannot help but root for him even when he is basically just committing large scale terrorism and/or murder as the terrorist Zero. His motivations are clearly defined to the audience so even when we do not have the inner monologue to go with it, we can see his thought processes and understand why he does each action. It is just fun to watch him play chess master and manipulate all of the pieces.
Lelouch is also interesting in that he does not want to be redeemed for his actions. He knows what he is doing is wrong but truly believes the end justifies the means. Yet he knows that once this is over, expects that he will be punished and almost wants to be punished.
However he is at his most interesting when things have not gone his way, as when Lelouch loses control over the situation he also loses his calm veneer and starts lashing out and what he does to get back in control can be devastating.
Grey Morality All Around
The motivations for each of the characters is rarely shown as just good or evil, there is usually a twist in the thread. The Black Knights commit terrorist acts but are seen as heroes to those in Area 11 as their saviors against a tyrannical oppression, which they are. However when their actions are seen through the lenses of the Britannians in response to civilian deaths they are seen as monsters, which they also are. Both sides are right.
The way in which these questions are asked in Code Geass on how to rid the world of its ills is usually left open for interpretation: to use extreme methods to combat the extreme views (such as the racism towards the "eleven's") or to use the slow approach and make people understand this is wrong rather than beat it into them. Neither method is advocated over the other, and rather than drawing a direct conclusion the show forces us to think about these issues more which can only be a strength.
Deconstructing the White Knight
Any other anime and this guy would have been the main character. Unfortunately for him, his role in this series is to show what lengths the role of a hero will go to accomplish this goal.
As the child of the former Prime Minister to Japan, Suzaku was exposed to the tragedies of war and the death that ensued. This trauma is carried with him now, culminating in a pathological desire to rescue others at the cost of himself as atonement for being unable to save so many.
Suzaku will always take the correct path and stands in direct contrast to Lelouch, he chooses to change the system rather than oppose it even though it means becoming an "honorary Brittanian" an outsider to the Brittanians planning whilst using his influence gained here to help the Japanese who see him as a traitor.
Throughout the series we are shown what it would mean to be the hero who tries to save everyone and watch it slowly consume him. By the start of season two Suzaku has changed becoming more ruthless. He admits the hypocrisy of his actions in working for Brittania but has started to gain the influence he desires. Suzaku arguably has the most character development throughout the series and it makes him a great foil to Lelouch.
Fantastic Mecha Designs and Fights
As a mecha anime enthusiast, Code Geass does not disappoint. I absolutely love the design of each the Knightmares from the Glasgow to the Lancelot, it being my particular favorite. However the Gurren is also fantastic and fun to watch in a fight. Each of the main characters has a more unique Knightmare to show how much of a badass they are and Code Geass lets them run wild. When these Knightmares fight they always take center stage and the choreography for each of the fights is some of the best I have seen for a mecha anime.
**MAJOR SPOILERS IN THIS SECTION**
The ending to Code Geass is one of the most thoroughly discussed and dissected endings to an anime that there is and with good reason. Lelouch's decision is thus: to liberate the world by sacrificing himself for the good of mankind, giving them a focal point for all of their hatred once he is gone so that the world can be free.
What I enjoy about this is that we get to see Lelouch play chess master one last time against the entire world. The rejection of Geass by both Suzaku and Lelouch is to show that the world does not need its power to change and can be viewed as a positive message. You don't need superpowers, anyone can change the world. This is the only act involving both characters that does not include the manipulation of others with Geass and yet is the largest manipulation in the entire series, the entire world, and the only one with a truly positive outcome. The story ties all of its loose ends and in particular why Lelouch 'Geassed' Schneizel to obey Zero as opposed to himself. Lelouch's death gambit to free the world gives us a very important anti-war message. If no resources were dedicated to fighting, humanity as a whole would improve which is referenced by Kallen in the epilogue. Of course this is juxtaposed by Nunnally who, having learned of Lelouch's plan can only tell her brother's body that she didn't want a perfect peaceful world, so long as he was a part of it, and it is heart rending to watch. Character deaths are hard but it is in keeping with Lelouch's mind set and is consistent with this characterisation. His belief that "the only ones who should kill are those prepared to be killed" has driven him to this point. He must die because he was prepared to die.
The greatest point I find in the ending is the characterization of both Lelouch and Suzaku. They have steadily changed throughout the series, each becoming more like the other. Lelouch using his influence (gained by rising in rank no less) to liberate Japan was Suzaku's dream, Suzaku freeing the world makes Lelouch's dream of a safe and kind world for Nunally a reality, and by the end they have finally switched roles in their entirety. Lelouch will sacrifice himself to save the world and Suzaku will murder him, to end all war. The ends justifying the means…
The ending is as painful as it is joyful, and is truly a masterpiece of storytelling.
"Yes... I... I destroy... the world... and create it... anew."
The Geass is as C.C describes it "the power of kings" and it manifests differently for each character based on their personality. For Lelouch this has given him the power to give one absolute command that any person shall obey, but he can only use it on a person once. This restriction is important as otherwise every situation could be solved by using the geass. Lelouch's refusal or inability to use it on certain characters like his sister leads to him having a supernatural power that is not a panacea. The Geass is an interesting power because it is adaptable and although it can be used to essentially move the story along (see the end of R1) this is usually not the case. The other Geass powers do vary in their variety and usefulness, Mao being the obvious example to turn to as his Geass stands as a counterpoint to Lelouch and allows for a story that could not be told without a supernatural power present. When the Geass is used like this, it shines brightest.
The Cast in General
I have only talked about a few of the characters so far but it would be unfair of me to say they were the only good and/or interesting ones. There is only one character that I do dislike (more on that later) but otherwise everyone is interesting. The only issue with some of these is that they can appear two dimensional just because they were left in the background a bit too long before being written out. We know the depth was probably there but we aren't allowed to see it. This is most painfully obvious with the Four Holy Swords, Tohdoh and Chiba are the only two given more than a few lines yet they are quite important to the Black Knights and it feels slightly like wasted potential.
The Fan Service
Well this IS a SUNRISE series. I have only put this here as your mileage may vary on this particular issue. I personally don't mind it when executed properly and it does not detract from what is going on or is just there for the sake of being there. However (this can be the case in particular), rear-shots of characters in their Knightmares make me aware that I am watching a TV show again and just ruin the immersion. Also of note is that whilst there is some attempt to make male fan-service this scale is clearly in favor of female fan service (as above). I am nothing if not fair.
The issue with pacing only really appears in R2. In R1 the pacing is almost perfect and each episode has enough time without feeling overcrowded, the plot points in each episode are examined thoroughly and then it moves on to the next one (although usually with a cliffhanger.) In R2 quite a few episodes are seemingly parts and whilst this is not a bad thing it can be a bit too much. The pacing in the last ~8 episodes becomes too fast. Once the final war starts and the allegiances of characters start switching it is fun to watch but too many events unfold at once so we are unable to step back and analyse them individually which is a step down from R1.
The cliffhangers are prevalent throughout the series (particularly the ending to R1) however this is not so much an issue in and of itself, but you might start expecting cliff hangers, so they lose some of their edge. They can still entice you into watching the next episode (and another and another....) so this is down to your individual opinion.
In case you cannot tell by choice of image, I do not like this character. She is openly racist towards Suzaku and the other Japanese, has a VERY one sided relationship with
a table Princess Euphemia, even becoming her stalker, and is responsible for a lot of damage in the second series. Although she might work out these issues by the end the damage is already done as she just started unlikable in the first place. Making a character realize racism is wrong doesn't make her a good character, it means that she has caught up to the rest of us. I also don't believe that someone with a genius intellect (her surname is Einstein to try and drive this home) would make racial slurs at the terrorists holding the group when she is a hostage.
Code Geass is one of the greatest anime I have ever watched and it does not lose its appeal on another viewing. Knowing what will happen does not lessen the impact of the story and I feel that that is the hallmark of a great series. The show appeals to so many because it caters to most without ever losing focus on what is important for any show, being fun.
Code Geass and Code Geass R2 are licensed by Funimation (US) and Kaze UK (UK). The series is currently available in both DVD and Blu-Ray format (at least in the UK).
Edit: Added the following Sections: [The Ending], [The Geass] & [Pacing]
Special thanks to ProtonStorm for helping me editing this article.