Clue: Writer of article starts to lose heart after foreign agreement (7)
Answer: ANOUILH
Explanation: Definition: Writer
AN (article) + OUI (French "yes", so "foreign agreement") + L[ose] H[eart]. Jean Anouilh, French playwright: I once played the heroine's sister in his play *Antigone* at my (all-boys) school. Fortunately there are no photographs or recordings of the event.