Mathieu Duflot is always on the lookout. In the metro and on the streets of Paris, this IT manager has picked up a thousand lost or discarded objects – "even a Cartier watch I sold at the Drouot auction house a long time ago for 40,000 francs [€8,500]," he said. But what he found on that Monday, January 14, 2002, at Nation metro station, on his way home from work, turned out to be more unusual. On the platform of line 6, a bundle of letters lay in a garbage can.

"From the yellowed paper and blue-white-red edging on some of the 'par avion' envelopes, I could see straight away that they were old letters," said Duflot. Without missing a beat, he snatched them up and took them home. It was in his sitting room that evening, looking at the documents in detail, that he realized just how unusual his find was: "All these letters in a dustbin, it was really strange. Some of them seemed very intimate. There was even a will in the pile."

His partner at the time, Florence Evrard, was intrigued and decided to find out more. Not for a moment did she imagine that her investigation would last for years, taking her into the secret world of Parisian lesbian cabarets, where she would cross paths with the shadows of Marlene Dietrich and Orson Welles, and discover the complex lives of homosexual women in the post-war years, nor that the little pile of letters would follow the death of one woman and herald another.

Twenty-two years after she first saw them, Evrard still considers the forgotten letters from the metro station her "treasure". In the apartment she still lives in, in eastern Paris, the 57-year-old fetched the delicate Japanese box in which she has stored everything, and carefully unfolded each document on the dining table. Dust more than half a century old tickled the nostrils.

There are 28 letters and postcards in all, dated from 1938 to 1976, with female signatures only, preceded by various tender words. "Your Maha who loves you with all her loving heart." "Many kisses, I hold you close to me. Ingrid." "I'm only thinking of you," writes Maria Luisa, a young divorcée and mother of one, who promises to send a lock of hair "as soon as [she's] washed [her] head."

Or from someone named Mireia: "My love, I miss you very much, much more than when we first separated." From Barcelona, Mireia states in the same letter that her husband has decided to leave her, which in no way saddens her: "It's difficult when a man and a woman live together without ever sleeping together." Other documents include a map of the Sarthe region, western France, cut out of a 1939 newspaper; the menu for an engagement dinner in April 1947; a recipe for fried rice, and a will. It's a strange mix.

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