who are you? a Gravity Falls story

When Mabel and Dipper turned 13 they left Gravity Falls and went back to California. instead of going back to Gravity Falls the next summer they had to stay in California with their parents,
However the summer after Dipper and Mabel go back to Gravity Falls now 14 years old, they are hoping to have great summer. But in an accident Dipper is shot with a memory gun and loses his memory, unfortunately his memory doesn't recover as quickly as Stan's did, partially because the memory gun wasn't made by McGucket. Mabel has to help her brother remember while working alongside Wendy, The gruncles, Pacifica Gideon, a new character, and a certain Bill Cipher. welcome back to Gravity Falls!