It's a really weird game. It takes place on a planet that has been wiped devoid of all life, and you play as the lone survivor. You are then granted, by the powers that be, the ability to restore life to the planet (sort of like Dark Cloud). But, that's about as cohesive as the plot gets. After that, the plot branches out in about a million directions, as you're sent on a countless number of sidequests.

If you give it a chance, it's a really cool game. The art direction is phenomenal, the characters are really great and there's a ton of stuff to do. If you're expecting a sequel to The Secret Of Mana, then you'll be disappointed. If you're expecting a beautifully crafted and extremely fun game, you'll love it.

I would make one suggestion to you before buying it, though. Buy the player's guide at the same time. If you don't, you'll find yourself really tangled up and confused as to what you should do next.