体贴入微的丈夫，温婉柔顺的妻子，一双如花似玉的可爱儿女，住在城郊的科尔曼一家，过着许多人艳羡的优渥生活。然而一切的宁静惬意，随着一场意外的流产，渐渐离他们远去。虽然这个尚未出世便夭折的婴孩，已经是他们家的第三个宝贝，但妻子凯特（薇拉·法米加）却怎么也无法摆脱这个阴影。一夜又一夜的噩梦和挥之不去的悲伤，几乎占据了她整个心灵，就连丈夫约翰（彼得·萨斯加德）的安慰也无济于事。
　　绝望之中，为了尽快走出梦魇，科尔曼夫妇决定通过福利机构收养一个孩子，以慰藉失去婴儿的痛苦。巧的是，在孤儿院，一个举止乖巧的女孩吸引了他们的注意。这个名叫艾丝特（伊莎贝拉·弗尔曼）的小姑娘，不但知书达理、画技精湛，还有着超乎年龄的早熟，简直就是最完美的孩子。于是，抓紧办妥了所有收养手续之后，艾丝特便成为了这个四口之家的一份子。
　　艾丝特的出现，无疑改变了科尔曼一家的生活。笑容重新回到了凯特脸上，约翰越来越喜欢这个贴心闺女，五岁的小女儿麦克丝（阿娅娜·安吉尼尔）更是成天黏着新姐姐，唯一对她心有芥蒂的，只有家里另一个“男子汉”--大儿子丹尼尔（吉米·本内特）。或许，他只是有些嫉妒被新家庭成员的到来抢去全家大小的注意力？然而，一切却随着艾丝特在学校被百般刁难而开始变化。欺负她的同学被推下楼梯，刻意疏远她的男孩遭到诬陷，多嘴多舌的修女惨死，一场熊熊燃烧的大火，甚至连包括科尔曼一家四口在内的所有人也开始接连被恐怖事件萦绕...，在艾丝特天使般的可爱面容下，到底隐藏着怎样可怕的答案？

Moonlight city. You just couldn’t see an end to it.
It wasn’t what I saw that stopped me ,Max.
It was what I didn’t see.

Take the piano.
Keys begin. Keys end.
You know there are 88 of them.
They’re not infinite. You’re infinite.
And on those keys, the music that you can make is infinite.
I like that. That I can live by.
But you get me up on that gangway, and you roll them out
in front of me.
Keyboards have millions and billions of keys that never end.
That keyboard is infinite.
Then on that keyboard there’s no music you can play.
That’s God’s piano.

Did you see the streets?
There’re thousands of them.
How do you choose just one?
One woman, one house, one way to die…….
You don’t even know where it comes to an end.
Aren’t you ever just scared of breaking apart with the
thought of it?

I was born on this ship.
And the world passed me by.
But 2000 people at a time and there’re old wishes here .
But nevermore that fit between prow and stern..
You played out your happiness bit on a piano that was not
infinite.
I learned to live that way.

Land?
Land is a ship too big for me,
It’s a woman too beautiful, a bridge too long, perfume to
strong, music I don’t know how to play.
I can never get off this ship.
At best, I didn’t step off my life.
After all, I don’t exist for anyone.