I'm in review mode so here it goes. This game is Blue Dragon. If you've played final fantasy or paper mario the gameplay is slightly similar. The game is littered with cutscenes and cinematics that translate into some large story. Inbetween these you have fights with monsters in an attempt to reach different points in the game and level up. The gameplay goes as such. You walk up to an enemy. Battle commences. Each of your characters attacks individually/uses items/defends and the enemy does the same. Turn order is dependent on a speed stat, how much damage you do on an attack stat, etc.
The idea behind the game's plot is that there is this one "evil being" who is trying to take over the world (novel idea). He wants all the power for himself, wants to restore magic as a dominating force, wants to bring war. You are a 10 (?) year old kid with his friends who wants to give the player of the game a good feeling about themselves as they try to "save the world from evil". You do this by using your shadow, which is a dragon.
Despite how ridiculous this sounds, the game is actually rather fun. I am biased in that Paper Mario and Paper Mario: Thousand Year Door (for the N64 and Gamecube respectively) are my favorite games, and the battle style / storyline is similar in format.
If you're looking for constant play this game isn't for you. You have to watch the cut scenes to really know what's going on. Admittedly the story is really kind of lame and the dialogue is absolutely horrible (comes out of a 10 year old kid's mouth, what do you expect). The plot twists are pretty easy to see in advance. But the graphics are solid, the gameplay is exceptional in my opinion. and the game is really open ended. Although there is structure so you're not always thinking to yourself "where do I go next", you can do things out of order without any real harm.
The in game achievements are really interesting. See all the monsters, collect all the items, etc really take time and dedication to the game, which is really rewarding if you do get it.
There are achievements for metagaming too, including killing dragons who are similar to the types of bosses you'd find in extraneous dungeons in Zelda.
Here's the biggest complaint I have personally and have read (besides the lame plot, but that's part of the lameness in playing this game, so it isn't a complaint). Anyway, this is it: Since you can decide which "dragon shadow class" you want to level up on each person (as in you can choose whether each person should specialize in being a medic/healer, physical attacker, special move attacker, barrier creator/protector), each person is so interchangable that the personalities of each character are kind of lost in battle, which is extremely important to the development of the story.
You wont be able to beat this game through a single rental, especially if you are going for even half of the achievements. If you feel it's your type of game, buy it. Apparently there is new DLC that lets you continue the game after you've "beaten" the story with your characters at the level they were at the "end" of the game through any of the thirty save points you've created. I never got around to it before I had to give the game back.
Game for the really dedicated gamer who likes games based on basic strategy, leveling up, and a deeply entrenched plot. If it doesn't sound like the game for you, it honestly probably isn't.