Summer 1910. Several tourists have vanished on the beaches of the Channel’s Coast. Infamous inspectors Machin and Malfoy soon gather that these mysterious disappearances take place in Slack Bay, home to a community of fishermen. Among them lives a curious family, the Bruforts, led by the father “The Eternal”, who deals as best as he can with his prankster bunch of sons, especially the impetuous Ma Loute. Towering high above the bay stands the Van Peteghems’ mansion. Every summer, this degenerate bourgeois family stagnates in the villa, not without mingling during their leisure hours with the local people. As a peculiar love story between Ma Loute and the young and mischievous Billie Van Peteghem begins, confusion and mystification will descend on both families, shaking their foundations.