Sorry for the double-post, but here's the story up to the demo's end.
You wake up in your small Pine Town house, play your new Wii for a bit, and then go downstairs for breakfast. When you go down, you see that your sister, Hope, is missing after she went to play in the woods by Lakefront. Your mother asks you to find her, and you go to Prof. Spruce's house. Prof. Spruce understands, but won't let you go to find Hope until you have a Pokemon. So, he walks you to the Lab, and allows you to choose between Breedling, Lantark, and Tadpond, then reminds you that you were going to leave on your Pokemon journey today, anyway. When you've got one, you go through Route 301, into Lakefront City, and into the nearby woods, where you find Hope singing to some wild Zapterfly. When she sees you, she realizes she has to go home, says goodbye to the Zapterfly, and says she'll tell Mom that you're setting out. You then attempt to go to the Lakefront Gym, but it's locked. So, since there's a battle blocking the exit of the Amber Forest, you go to Derukia Lake, to see Elliot of Lakefront Gym battling some strange men, who notice that the Balance Scepter isn't in Derukia Tower, then leave for Chromeshore, and their base. Elliot leaves, and you walk to his Gym, where you beat him handily. You then go through Amber Forest, to Breezetop Town, where you defeat the Gym Leader, Morph, on your way to Chromeshore. On your way, you stop in the scenic Saltlake Town, built on a salt lake created in a flood. You cross the Derukia Strait, then arrive in Chromeshore, which is controlled by the people you saw at Derukia Lake. The gym, the Runil Co. Office Building, and the Poketain Building are all locked. You'll see that there's some commotion at the mine, and enter. After beating off GENESIS grunts with a stick and learning of their plans, you see the mining chief and Gym Leader Cyan and the miners being interrogated by the head of GENESIS - your father, and hear something about a secret order of ancient Guardians of Derukia Tower. Cyan admits to being part of it, and is then made to surrender a map to the Balance Scepter before the GENESIS members depart. Cyan chuckles, and explains that it's written in old Derukian. Then, realizing that he's too old to journey himself, he asks you to carry the only known book that contains a text in both old and new Derukian, and carry the sacred duties of a Guardian of Derukia Tower. You accept, before beating him in his Gym and learnimg that the Balance Scepter now rests deep inside Greataltar Temple...