Synopsis by Hal Erickson
The second episode of Lost in Space picks up where the first one left off, as the Jupiter 2 is thrown off course by the sabotage efforts of enemy agent Dr. Smith (Jonathan Harris)--who, in fine "hoist on his own petard" fashion, has been trapped on board the ship along with the Space Family Robinson and their pilot Don West (Mark Goddard). Although Maureen Robinson (June Lockhart) has successfully rescued her husband John (Guy Williams) from drifting helplessly in space, the family isn't out of danger yet, thanks to a comet which is rapidly approaching their vessel. And in a later development, the family faces new perils from a group of strange, bubblelike creatures in a huge alien spaceship. In addition to utilizing stock footage from the original Lost in Space pilot (in which Dr. Smith did not appear), this episode features a portion of the "giant human brain" set from the 20th Century-Fox theatrical feature Fantastic Voyage--which hadn't yet been released when the episode originally aired!