Franklin is on holiday and is delighted by a surprise visit from his Aunt Lucy, an explorer whose specialty is finding archaeological treasures. Her presence promises passionate adventures. This family reunion gives Franklin's Granny the chance to relive her own childhood, full of happy souvenirs but also very sad ones, like the day when her parents died in a forest fire. This is when she mentions a box filled with treasures that she had hidden and buried. Franklin is of course intrigued. The treasure hunt becomes extremely important when Granny falls ill and Aunt Lucy remembers a remedy that might just be in that famous box of treasure. Franklin decides straight away to go on the hunt for this Talisman which could save his grandmother. His friends Beaver and Bear accompany him, with Aunt Lucy of course... but they are not alone. Samantha, Aunt Lucy's goddaughter joins her for the holidays and this little turtle with a very strong character bothers our friend Franklin... It's not the only difficultly he encounters on the way, but Franklin is ready to do anything in order to find Granny's secret ... and its all for the best as it gives him the chance to make new friends.