Fresh out of college with hopes of an exciting summer, Lindsay begins nannying for a wealthy family on Martha's Vineyard. As the summer progresses, Lindsay develops an unexpected bond with the eldest child, Georgia. That is until a traumatic event unfolds, terrorizing their friendship. A decade later, Georgia is ready to break her silence and help her former nanny seek justice. Julia Spiro's Someone Else's Secret touches on similar themes to those found in Firefly Lane, like female friendships, ambition, and survival.