2 films match Frantic

A doctor and his wife go to Paris for a medical conference. While showering, his wife disappears.

Florence Carala and her lover Julien Tavernier, an ex - paratrooper want to murder her husband by faking a suicide. But after Julien has killed him and he puts his things in his car, he finds he has forgotten the rope outside the window and he returns to the building to remove it... (imdb)