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THE INTERNAL SEA: Mare Internum where the divide between the living and the dead is more transparent – and delicate – than humanity ever suspected.


Journey to the Center of the Earth meets Ghosts of Mars in the supernatural science fiction mystery on Mars, THE INTERNAL SEA: Mare Internum where the divide between the living and the dead is more transparent – and delicate – than humanity ever suspected.


Life on Mars…

No man is an island entire of itself, but Dr. Michael Fisher, a disgraced planetary geologist living on Mars, has never felt more isolated. The situation worsens when both he and Dr. Bex Egunsola, the station’s newest biologist, accidentally break through the floor of an unstable lava tube into an ancient subterranean world… and they are not alone.

Is this purgatorial abyss a prison or a sanctuary? Genuine or constructed? How thin runs the line between life and death? And is there a chance for the fallen to return to the world of the living?

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The Creative Team


Der-shing Helmer is an Eisner and Ignatz winning indie comic creator and publisher who mostly creates science-fantasy and educational comics. They are the creator/ artist of the acclaimed webcomics The Meek and Mare Internum, creator/ editor of the Alloy Anthology, and co-owner of Ascend Comics. Their favorite way of participating in everyday science is learning how to grow rare plants from seed, and sharing plants and knowledge with others.

Book Details

  • Writer: Der-shing Helmer
  • Artist: Der-shing Helmer
  • Colorist: Der-shing Helmer
  • Letterer: Der-shing Helmer
  • Genre: Science Fiction
  • Publisher: Vault Comics
  • Distributor: Simon & Schuster
  • Pages: 320
  • Publication Date: September 9, 2025
  • ISBN: 978-1638492979
  • ASIN: B0DY926MC4

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