A number of characters from .hack//SIGN and .hack video games come together for a big party in Cyber Slum.
Taking place after the end of the .hack video games, "Unison" is more or less an epilogue to both the games and the TV series. Helba invites Tsukasa, Bear, BT, Mimiru, Subaru, Silver Knight, Sora, Crim, Kite, BlackRose, Mistral, Balmung, Orca, Elk and Mia to a huge party in Net Slum. Some characters reunite, some meet for the first time, and everybody gets their funk on. (Source: ANN)