When The Map Was Unrolled, The Dagger Was Revealed

During the Warring States Period, the Ch'in army was drawing very close to the border of Yan. So the crown prince of Yan took a map of the Yan city of Du-kang, and rolled a dagger up inside. He then gave it to a man named Jing Ke, ordering him to take it into Ch'in and kill their king.

Meanwhile, the Ch'in general Fan Wu-chi insulted the king of Ch'in. The king offered a very large reward for his head, and so Fan fled to Yan to escape. When he heard about Jing Ke's plan, however, he decided to sacrifice himself for the cause, and slit his throat, committing suicide.

And so Jing Ke took Fan's head, along with the map of Du-kang, and presented them to the king of Ch'in, surrounded on all sides by armed guards. When the king saw the map, he thought that Yan was ceding territory to him, along with offering him Fan Wu-chi's head, and he was very pleased. He immediately unrolled the map, revealing the shiny bright dagger. Jing Ke grabbed the dagger and stabbed at the king. Unfortunately, he missed the king and hit only his sleeve. And so two heroes had sacrificed themselves for their countries.

Today, this idiom is used to mean that a person's plan is completely exposed, and there is no way to cover it up.

圖窮匕見

戰國末期，秦國很強大，在消滅了趙國後，打到北部的燕國，燕國岌岌可危。

燕國的太子丹請荊軻去刺殺秦王，並派勇士秦舞陽作荊軻的助手，讓荊軻帶著秦王的仇人樊於期的人頭和燕國督亢的地圖作禮物，將一把毒藥熬過的匕首藏在地圖裡。

荊軻和秦舞陽二人到了秦國，買通了秦王左右為他們引見，秦王很高興，就在咸陽宮接見他們。在登上宮殿的台階時，秦舞陽緊張得發抖，荊軻就把他留在外面。

秦王看過仇人樊於期的人頭後，又要看地圖。荊軻捧著地圖來到秦王面前，獻上去。秦王慢慢展開地圖來仔細看，當地圖展到盡頭時，藏在裡邊的匕首露了出來。荊軻迅速一手抓住秦王的衣袖，一手抓起匕首刺向秦王。秦王扯斷了衣袖，轉身逃走，荊軻就在後邊緊追。這時，秦王的衛士們趕來了，荊軻受了傷，就把手中的匕首投向秦王，但沒有擊中。最後荊軻被衛士們殺死了。

「圖窮匕見」比喻事情到了最後，真相終會暴露出來了。