- Hilarious in Hindsight:
- Terry Nation would later create a series where the main characters use teleportation bracelets.
- The Doctor travelling to various locations to find a series of keys, in order to serve the greater good, only for the whole thing to turn out to be a "Shaggy Dog" Story? Years later, the Fourth Doctor spent an entire season acting out that storyline!
- Special Effects Failure: The ice on the cave walls is represented with clingfilm stretched over the set. It's quite obvious, but is also forgivable... except for how when the actors run through the the caves, every step makes that distinctive clingfilm squeak.
YMMV / Doctor Who S1 E5 "The Keys of Marinus"