1x1 - Vanished by the Lake

Lise Stocker, head of the Paris Crime Bureau, returns to her hometown to care for her sick mother. Upon her return, she hears that local teenager, Chloe, has vanished during a local celebration. The mystery disappearance ignites old memories for Lise - fifteen years ago her two best friends, Ana and Marion, disappeared during the very same event. Is there a connection between the two incidents?