Dom François Plaine (1833-1900), a specialist in the hagiography of Brittany, corresponded with the Bollandists Victor De Buck, his brother Remi, Charles De Smedt and Albert Poncelet between 1871 and 1893. After a stay in Brussels he played a part in the beginnings of the Analecta Bollandiana (1882-1889). An end was put to the collaboration by De Smedt because of irreconciliable methodological and conceptual divergences. Plaine, who had been schooled in traditional apologetics at Solesmes, could not understand the critical spirit promoted in the Bulletin des publications hagiographiques under Poncelet’s influence from 1891. The virulence of their exchanges in some ways foreshadows the modernist crisis, which brought about the surveillance of the Bulletin by Rome up until 1920.