While crowds streamed into the Hong Kong Book Fair on July 15, elsewhere in the city, national security police and customs officers raided two independent bookshops, seizing novels and arresting five people for alleged sedition. It is a bleak contrast. While the government made a public show of celebrating books, it was simultaneously punishing booksellers for what they placed on their shelves. Hong Kong officials have also refused to specify which books are illegal. This uncertainty does much of the censoring work for them—fear sparked by one arrest prompts other shops to preemptively remove unbanned novels. What disappears is not only a business, but the freedom to compare conflicting accounts of the past and encounter ideas that the government rejects, reaching independent conclusions. With every missing book, the horizon of what Hongkongers can know, question, and imagine grows narrower.