图穷匕首见tú qióng bǐ shǒu xiàn(lit.) the assassin's dagger, concealed in a map scroll, is suddenly revealed when the map is unrolled (referring to the attempted assassination of Ying Zheng 嬴政 (Yíng Zhèng) by Jing Ke 荆轲 (Jīng Kē) in 227 BC) (idiom)↗See 图穷匕见WordUnreviewed