Several sources, including IMDb, state that Nielsen played Mata Hari in an early-1920s film variously titled "Mata Hari", "Die Spionin" (‘The Spy’). However, scholarly works such as the authoritative filmography published by Filmarchiv Austria in 2010 make no mention of such a film. Film scholar Ivo Blom has concluded that the idea of Nielsen playing Mata Hari on film arose from a confusion with her now-lost film "Die Tänzerin Navarro" (1922), which features a plot similar to the story of Mata Hari's life.