This is sort of a "1930s Serial as done by Irwin Allen". Imagine what Republic or Mascot could have done with 1970s movie technology. Superb special effects, the acting ranges from good to hammy, the dialog often inane, the premise preposterous, but if you don't take it too seriously, it's fun, a good rainy/snowy afternoon entertainment. It does contain one of my favorite movie scenes however. When the two Navy officers awaken Captain Nemo and he starts to talk about his crew and his ship, one of them says: "But Captain Nemo was a character in a book by Jules Verne!" To which he replies: "Had it perhaps occurred to you that that writer was a biographer as well as a novelist?"