Object
Voord Glass Submarines (Fish-Shaped One-Person Submarines)
Transparent, fish-shaped submarines that enable the Voord frogmen to infiltrate the pyramid underwater. These vessels are built for single occupants to navigate the corrosive acid sea of Marinus, featuring a sleek, metallic design with glass elements. Barbara identifies them as the intruders' transport, prompting Susan, the Doctor, Ian, and Arbitan to recognize the Voord as external threats rather than building defenders. The submarines' appearance on the glass beach—where Ian and the Doctor force one open, exposing a dead frogman in a ripped protective suit—confirms the lethal planetary conditions and reveals the presence of an advanced civilization. Their discovery drives the crew inland to investigate the pyramid amid rising threats.
2 appearances
Purpose
Transport Voord frogmen for undetected infiltration of the pyramid
Significance
Clue that reframes Voord as offshore invaders, escalates pyramid vulnerability, and forces TARDIS crew into alliance with lone guardian Arbitan against relentless assaults
Appearances in the Narrative
When this object appears and how it's used