In the small coastal town of Grey Harbor, five lifelong friends are about to spend their last summer together before life pulls them in different directions. What starts as a nostalgic farewell turns into the adventure of a lifetime when they stumble upon an ancient pirate map. As they chase after hidden treasure along the rugged coastline, they discover much more than gold - they unravel the mysterious history of their town, uncovering a centuries-old feud between rival pirate families and dark secrets that have been buried for generations.
But the treasure hunt isn't the only thing testing their friendship. Old wounds resurface, unresolved feelings are confronted, and the uncertainty of their futures looms large. Eli, Cassie, Ben, Maya, and Toby must navigate not only treacherous terrain but also the shifting dynamics of their bond, which has held them together since childhood. As tensions rise and the stakes grow higher, they realize this summer is about more than just treasure - it's about facing the past, embracing the unknown, and discovering who they truly are before they say goodbye.
With every clue they uncover, the group inches closer to the truth behind the legendary treasure, but they aren't the only ones seeking it. A descendant of one of the pirate families emerges from the shadows, determined to reclaim the treasure for their own sinister purposes. What began as a fun adventure becomes a high-stakes race to protect the legacy they've uncovered.
As fireflies light up their final night together, the friends reflect on how far they've come - not just on the treasure hunt, but in their own lives. With the treasure buried, friendships tested, and a bittersweet goodbye on the horizon, Firefly Glow is a coming-of-age story filled with mystery, adventure, and the poignant beauty of growing up and moving on. Can they hold onto the memories and the magic of their friendship, or will this summer be the last time they truly shine together?