The Doctor's Secret (French: Hydrothérapie fantastique) is a 1909 French silent trick film by Georges Méliès.
It was sold by Méliès's Star Film Company and is numbered 1476–1485 in its catalogues.
[1] Méliès appears in the film as the hydrotherapist.
Photographic evidence suggests that the film was a new version of an unidentified Méliès film from around 1900, for which two stills survive at the Cinémathèque Française.
[1] The bathtub prop was reused from Méliès's 1907 film Rogues' Tricks; special effects in the film were worked with substitution splices, stage machinery, and pyrotechnics.