The only episode of the series without a teaser segment at the beginning. It starts with the title sequence and then moves directly into the first act. The episode's title and writer and director credits, usually shown at the beginning of the first act, are displayed at the beginning of the second. The explanation is that the first act was the teaser in the original cut of the episode and the second act had been the first. At about 7-1/2 minutes long, CBS considered it too long for a teaser and moved it behind the title sequence to make it the first act and make the first act the second. This revised cut was later used in the syndication release and the 2005 DVD release. For the 2015 blue-ray release, the original cut was restored. The original cut was also aired in January 2022 on MeTV.
This is the only chapter in the opening 5-part serial that does not include footage from No Place to Hide (1965).
Thinking that the alien ship contained colleagues, Dr. Smith radios them using the pass-code "Aeolus-14-Umbra." It is perhaps prophetic. In ancient Greek mythology, Aeolus was the ruler of winds who lived on a floating island. He provided Odysseus safe passage home by capturing all conflicting winds in a bag, but just as Odysseus and his fellows were about to get back home, the bag was opened, blowing their ship right back to its previous position. Thus it may be that the Robinsons aboard the alien ship - a floating island in space - were about to find their way back home (via John and Don's exploration of its navigation center) till Will and Dr. Smith's disastrous encounter with the inverted-bag-like aliens, thrusting the castaways back into space, no closer home than they were before.
Later, in The Prisoners of Space (1966), the encounter with the "bubble creatures" is replayed within a tribunal setting in which a bubble creature sits in judgment of the Robinsons.
Penny is listening to William Shakespeare's Sonnet 18