Linkeroever (2008)

A world-class runner gets more than she bargained for when she moves in with her boyfriend in the Belgian mystery flick Linkeroever (Left Bank) (2008). Eline Kuppens stars as Marie, a 22-year-old athlete who meets charming archer Bobby (Matthias Schoenaerts) at the track. Their relationship progresses quickly, and when Marie comes down with chronic fatigue syndrome and can no longer train, Bobby offers for her to move in with him. But his apartment building houses a horrifying secret, and by the time Marie discovers what it is, it may already be too late. The trim, toned Elaine goes full frontal in the shower, having athletic sex with her guy, and swimming in some underground caverns, making Linkeroever a feast of nude pleasure.