Best Friends is the fourth novel by Ann M. Martin in the Main Street series. The main character, Flora Northrop, is excited for the 350th anniversary of Camden Falls. Even better, her best friend Annika is coming to visit! Flora hasn't seen Annika since her parents died in a car crash and they went to live with her grandmother, Min. However, her new best friend, Olivia, is worried that Flora will like Annika better than her, and that Flora will regret coming to Camden Falls.