Public domain. Cover image from Project Gutenberg ebook #74086. The invisible master by Edmond Hamilton Download .m4b · 80 MB How to listen → · Problem with this narration? Let us know → Narrator Walter — American Narrator (en-US) Length 1 hr 18 min Language English Added November 3, 2026 Source ebook Project Gutenberg License Public domain FictionMysteryScience Fiction