Mack, Brady and their new friends Robin, Sydney and Ryan receive a surprise visit from the Wet Side Story gang. But how to get them home? Can they afford for them to stay? Where will they sleep? One simple solution somehow gets them involved in the mysteries of Gravity Falls. Will any of the secrets hidden in this strange town somehow explain the weirdness of that summer?

Two sisters reunite when one of them decides to follow the other one's steps at the Choosing ceremony. Grace is looking forward to meeting new friends and transforming into a new person, while Martine is trying to deal with some new problems that suddenly come up in her job. How is their life going to look like now and how will they affect the Divergent characters?