In the game, the player takes the role of an unnamed former little senior league baseball ace who lost his or her baseball career after suffering an unspecified injury. The character moves to his or her grandmother's hometown and enrolls in the local high school, resolved never to enter the world of baseball again. When the character meets Tsubasa Arihara, he or she is persuaded to be the manager of the school's baseball team, and to take the team to the high school nationals at Koshien. (Source: ANN)

The characters from previous .hack//G.U. Games and .hack//Roots receive an email from Ovan. He is requesting them to go to Hidden Forbidden Festival where is set up a mysterious summer festival. There they find an AIDA Chim Chim who wishes to peacefully co-exist with the other players of The World. It then transforms into the word Returner, so they assume it to mean that Ovan will return to The World. (Source: ANN)

As an expression of gratitude for the heroes of both the .hack//Sign and the .hack game series, Helba has prepared a special event for all the characters to find the newly established Twilight Hot Springs. The characters can get their well-deserved rest and relaxation by having a soak in the wonderful hot springs, but there is only one problem—the hot springs are hidden, and there have been mysterious player murders. With the only clue being the word GIFT, the race has begun to find the culprit and the location of the hot springs.

Hacka Dolls are AI that scan a person in order to tailor news recommendations and information to their users. These widespread, personalized robots have served many citizens, from government officials to professional sports players. A severe drop in quality leads to the production of three substandard Hacka Dolls. Due to their personality defects, they are sent to Earth, tasked with advancing humanity in whatever way they can. Whether it be encouraging a fujoshi to sell a doujinshi at Comiket or performing in an idol group, the three dolls will complete any task as long as it abides by their moral compass. Despite their shortcomings, they take their mission very seriously and always try their best to assist everyone with incredible enthusiasm.