French-English translations for vendre la mèche

blab
let the cat out of the bagOtherwise people may come to believe that Mr Weisglass was right and that his only mistake was to let the cat out of the bag. Autrement, d’aucuns pourraient être amenés à croire que M. Weisglass avait raison et que sa seule erreur a été de vendre la mèche. It was going to be a surprise party until someone let the cat out of the bag.

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