In three chapters, Andre Techine's The Witnesses relates how a tightknit group of French friends reacts to the onset of Aids in 1984-85. They're a successful fiftysomething gay doctor (Michel Blanc), his close confidante, a children's author (Emmanuelle Beart), who resents the attention his small child demands, and the writer's partner, a handsome vice-squad inspector of Arab origins (Sami Bouajila). Trouble comes when an attractive provincial teenage lad is taken platonically under the masochistic doctor's wing and enters on a passionate sexual relationship with the cop before developing full-blown Aids. It's subtly observed, positive and unsentimental.