In 'Hello, Goodbye!', players find themselves in a seemingly mundane chat application that allows them to converse with various personas from their past, present, and future. However, this ordinary interface unveils a dark twist: the conversations unfold with unexpected and often chilling turns. Players must navigate their memory, confront unresolved issues, and piece together a hidden narrative that reveals a dangerous truth lurking beneath the surface. As players interact with friends, enemies, and themselves, they must make choices that alter their emotionally charged experiences, leading to multiple endings based on the paths they choose.