The movie starts in the present day, with Lisa (played by Julia Roberts) and Charles (played by Willem Dafoe) travelling together for Lisa’s graduation, when an accident takes place and Lisa is killed, while Charles is injured. The family comprises of Lisa and Charles’ children, Michael (played by Ryan Reynolds and Cayden Boyd as the old and young versions respectively) and daughter Ryne (played by Shannon Lucio). Then there is Lisa’s much younger sister Jane (played by Emily Watson and Hayden Panettiere as the old and young versions respectively), and her son Christopher (played by Chase Ellison) and Leslie (played by Brooklyn Proulx). There is also Michael’s ex-wife Kelly (played by Carrie Ann-Moss).
The accident with which the movie starts off is a result of Christopher, Lisa’s nephew carelessly walking across the road. So as to avoid him, Charles has to swerve the car into a tree, which results in the death of Lisa. What follows is a constant switch between present day and flash back. Charles and Michael are shown to have a strained relation, which has grown worse over time. Charles as a father has always been a domineering figure who has earned the ill will of most of the family members.
As a result, the entire family together is like a nuclear bomb about to go off. With secrets being unearthed and family members boomeranging off each other constantly, one feels like they might self-combust. But, gradually with each truth that is learned the family grows closer together, with the eventual reconciliation of Michael and his father Charles.
The movie title is taken from the Robert Frost poem of a same name, which as a child Michael claims to be his own creation so as to embarrass his father in front of his friends. However, once he grows up he writes a novel with the same name – Fireflies in the Garden, which would have been a manuscript of his and Jane’s tough childhood because of Charles. But, when in the closing scenes, Michael walks in on the whole family viewing a family video, he is surprised by the happiness it captured, and decides to scrap the manuscript, and rekindle his relationship with his father.
Even though the movie keeps moving back and forth between past and present thereby getting a little confusing and hard to follow, the overall theme is interesting and an enjoyable watch, especially once you remember which actor plays which character.