I have scores of reference books on French language, literature, art, history and so on, yet I find myself pulling this one out almost as often as the rest put together.
Do not let the admittedly high price put you off. Its 865 pages of fairly small print are packed with superbly concise entries on everything you can think of and more besides, like history and cinema. Heaven knows how the editors managed to get it this good first time. One reviewer called it the best work of its kind in the English language: I have yet to see one this good in French!