Prince Caspian, the rightful heir to the throne of his father, is hiding in the woods with the Narnians, as his uncle, King Miraz, is plotting to kill him when the latter's wife gave birth to a son.
With the help of the Narnians and the Kings and Queens of Narnia, Prince Caspian embarked to an adventure, finding Aslan, battling with the Telmarines and restoring the magic and glory of the land.
Personally, I think this is better than the first one regardless of reading the book. Based on the film itself, the director had done a great work. Watching the battle scenes, it seems to me I am watching Warcraft, if you used to play the game you'll know what I'm talking about, or Lord of the Rings perhaps.
Well, I guess it's up for you to decide then.