Jupiter's thigh (1980)

Antoine, a professor of Greek, and Lise, a police inspector, honeymoon in Greece. There they meet a young couple, Charles, an archaeologist, and Agnes, a dishy flirt. Charles unearths the lovely buttocks of a classical statue and is determined to donate it to the Louvre. Agnes wants to sell it and gets a handsome local sailor to take it for an appraisal. When the sailor is murdered, the police suspect Charles and arrest Antoine as his accomplice. Lise swings into action, but before she can clear the men, Agnes springs them from jail, and now Lise must help them elude the police, find the real murderer, and recover the statue fragment. More art goes missing. What is the statue's secret?