This article aims to read Taiwan’s 2019 cinematic horror sensation, Detention, as part of the nation’s effort to construct a grand narrative of collective commemoration, as it tries to streamline its multiple conflicting memories about the Nationalist government’s violent political suppressions of suspected dissidents during the mid-20th century, commonly called the White Terror. For this nationalist narrative to follow the Gothic scenario of progression from repression to liberation, embarrassing elements of the past, especially many White Terror victims’ sympathy with the Chinese Communist Party, must be de-politicized and dis-remembered. The movie adopts a ploy that can be called “isomorphic camouflage” in presenting its scenes and characters to evoke most viewers’ impressions about the White Terror while removing their actual political significances. This Gothic agenda, however, confronts its traumatizing point at the center of the movie, its female protagonist Fang Ray-shin, whose “ignorance and innocence” ironically expose the limitation of the nationalist collective commemoration