这是一个被巨人支配着的世界。成为巨人的食物的人类建造起了高达50米的巨大墙壁，以自由为代价去防止墙外的巨人的侵略。10岁的少年艾伦·耶格尔梦想着看到未知的墙外的世界。艾伦对那些满足于暂时的和平而放弃外出的人们感到格格不入。艾伦称他们为“家畜”。他们认为艾伦是“异物”。但是，由于能跨越墙壁的超大型巨人的出现，艾伦的“梦想”和人们的“和平”都瞬间土崩瓦解了。
The green Verdies are the tiny, but brave guardians of the lakeside. The young Verdies only become guardians when their hair turns brown. Until then, however, life is boring. The youngsters with green hair are not allowed to fly on warblers, not allowed to row alone, and they're not allowed to ride wild frogs at the rodeo. Willy Whistle's big dream is to become a guardian, but his curiosity always gets him into trouble. However, the whole lake becomes at risk when the enemies of the lakeside, the Grimps and the swans, enter into alliance. The guardians are helpless, but Willy comes up with a daring plan in order to save his home and his trapped friend, Jeremiah Jump. Luckily he is not alone, because Grandpa, the water snakes and the frogs also come to his aid.
