In the best surrealist tradition, the opening credit of The Exterminating Angel warns that "from the standpoint of pure reason there is no explanation" for Buñuel's brilliant, disconcertingly funny joke which forms the premise of this film. Guests at a bourgeois party following an evening at the opera each find some mysterious compulsion making it impossible for them to leave. "No explanation" certainly, but there are meanings aplenty in Buñuel's powerful central image of decay as the vast, bourgeois salon is reduced to a sordid rubbish-heap. Is the decomposition of the rational thinking a veneer of civilisation?

This breakdown, along with issues of class, social customs, sexual relationships and the role of religion are examined (significantly, the whole thing takes place under the sign of the Church).

One writer has suggested that The Exterminating Angel works as an extension of the salon sequence in L'Age d'Or, and many consider these two films to be Buñuel's best. Devastatingly funny, illuminated by unexpected shafts of generosity and tenderness, it remains one of Buñuel's finest.