While fans were introduced to the young, 1st class SOLDIER, Zack, in Final Fantasy VIII, much of what happened in the past remained a mystery. That is, until Crisis Core, where Zack's background is fleshed out in order to better explain things.
At the beginning of the game, Zack is just a 2nd class SOLDIER, trying to become a first. But more than that, Zack wishes to be a "hero." He goes on various missions, but much to his dismay, he is not really recognized, even if he does play a big part. Instead, the great 1st class SOLDIER Sephiroth gets all the praise.
During Zack's time in SOLDIER, he has looked up to a particular 1st class, by the name of Angeal. Angeal has helped Zack a great deal and the two of them become great friends. However, after a particular mission, Angeal goes missing, and Zack begins to worry. While Sephiroth makes speculations that Angeal is helping a SOLDIER, by the name of Genesis, who recently ran off and stole some of the SOLDIER troops, Zack finds it hard to believe, even though the great Sephiroth speaks these words.
Thus, Zack gets thrown into many missions in order to find out not only where Angeal has gone but also to track down the missing 1st class SOLDIER, Genesis.
Angeal is not only a 1st class SOLDIER, but also a mentor to other, lower-ranked soldiers. He is a mentor to Zack and helps to teach him the ways of SOLDIER, but not only that, Angeal conciders Zack to be a good friend, even though they are of diffrent ranks.
Angeal is good friends with two other 1st class SOLDIER's, Sephiroth and Genesis. The three of them seem to get along quite well. Which is to be expected. Angeal has a very gentle and kind personality, which makes it easy for him to gain the trust of those around him.
Angeal grew up in a small, country-side home. He was very poor growing up, but he never let it get him down. Instead, it allowed him to focus on the simple pleasures that life brought him, those which could never have be bought with money.
Angeal is the original owner of the Buster Sword, the famous sword which Cloud wields in Final Fantasy VII.
Any fan of the original game will know Sephiroth far too well. Sephiroth, the famous 1st class SOLDIER, is actually a so-called "good guy" in this game. Sephiroth's role in this game may not be as great as it is in the original, but there is still some importance in it.
Sephiroth is good friends with two other 1st class SOLDIERs, Genesis and Angeal. The three of them seem to get along quite well.
As would be expected, Sephiroth is looked up to by many of the lower class SOLDIEr working for Shinra. Not only that, but this silver-haired man seems to have a lot of female fans in town. He is somewhat of an idol to many of the people living in Midgar.
Genesis first appeared in the "secret ending" of Dirge of Cerberus. What is interesting to note here, is that the secret ending was FMV, however, it had live-action acting, that done by Gackt Camui. Genesis' design was actually based off the Japanese Pop star. In the Japanese version Gackt also did the voice acting for the character. So if Genesis looks too overly familar, that may be why.
The character himself is a 1st class SOLDIER who is good friends with both Sephiroth and Angeal. Genesis is very found of a certain play, by the name of LOVELESS. He often goes around reciting various stanzas from the play.
Genesis is a result of the Project G, which was done by Gast, Lucrecia, and Hojo. He seems to share similar traits to Sephiroth, such as having one wing, only his wing is black instead of white.
At the beginning of the game, Zack learns that Genesis has gone missing, and Shinra is trying to locate him.
There is also a fanclub for Genesis, which Zack can join by talking to some female fans in town. It is called the "Red Leather Fanclub." He'll get e-mail newsletters and updates. :)
Lazard is a new character in the series. He's the head of the executive Department of SOLDIER. He oversees SOLDIER's management and draws up rought strategies and guidelines. Which means, basically, he issues most of the orders to the moments of SOLDIER. Lazard does not have any combat skills and is quite frail, therefor he does not take part in any of the SOLDIER missions front-hand.
Known as either Aerith or Aeris, depending on which you prefer, she is a young woman who Zack meets on his adventures as a SOLDIER for Shinra. As you should known from the original game, Aerith becomes quite attached to Zack and she regards him as her "boyfriend." The two of them share many moments together in this game.
Though he was the main character in the original game, Cloud takes on more of a supporting-type role in this game. The interaction between Zack and Cloud shows the roots of the two's friendship and how things came to be.
In this game, Cloud is merely a low-ranked SOLDIER who had just recently join. However, Zack shows a great amount of kindness to the spiky-haired young man.