The story was great, but they made one major screw up that damaged the episode severely. When the Seaview loses power, crew members are shown using flashlights, so batteries were obviously not affected by the Ion Pulse. FLASH: Nuclear submarines all have back-up batteries that can allow the sub to function for up to 4 days, or longer if power consumption is reduced (and this was true in the 1960s as well). Even the Nautilus had back-up batteries. Also, all Nuke subs have an auxiliary diesel engine that can be used as temporary surface (or snorkel) propulsion, but mainly to recharge the batteries. If nothing else, the batteries can be used to blow the ballast tanks for an emergency surface. Then, the attacking forces could have been been signaled to stand down, either by radio, or visually.Mistake 2: The ballast tanks work off of compressed air, which can be blown manually both into the ballast tanks, and into the sub for life-support. They would've been fine on life-support for a week, or longer with just the air in the compressed tanks. I realize it is a Science Fiction show, but these systems have been standard equipment on all subs since the mid 1930s. It really hurts the believability of an otherwise outstanding story.

This is a well thought out episode. It examines the human fear of the unknown. I will not reveal the plot, but I can say that the philosophical implications are as timely, maybe more so than in the 1960's. The struggle between the pursuit of aggression or the choice of peaceful aid is exemplified in this teleplay. While the "special effects" may seem laughable by today's CGI technology, the message in the episode is what is really meaningful. I always enjoyed Richard Basehart's acting, and it's hard to believe that he left us 25 years ago this year, right after doing the live narration of the 1984 Olympic Games in Los Angeles.
I didn't get a chance to see these early broadcasts of the series when they were originally aired on ABC. The general consensus is that the first two seasons were the best. Later, when the series went to color, Irwin Allen decided to "monster" it up. Well, a few intelligently done episodes are better than none. Incidentally, there is only one character depicted in "Falling From the Sky" where the studio make-up people showed their considerable skill.