This SF essay explores the near-future of the digital virtual world where the mnemonic power of analog photographs, which guarantees indexicality, is no longer effective. It unfolds under the theme of "migration," where memories are erased in the digital world to enable happiness. The issue of migration poses the question of whether erasing historical, political realities, and identities is a prerequisite for integration into a new society. On the other hand, the film understands photography as a medium that can only prove the past exists alongside the acknowledgment that there was a certain reality. It raises questions about the validity and trustworthiness of photographs as a means to remember a reality that has turned into the past. In the context of Across the Border, the problem of memory being invalidated is crossed with the problem of photographs losing their validity and trustworthiness. The film attempts to critique 21st-century culture by intersecting these two cases of memory denial within a virtual drama.