Lost in Space premiered when I was six, which is probably the optimal viewing age for that show. (Talking vegetables, anyone?) So naturally I was hooked. I was a bit too young for Star Trek when it appeared the following year, but, like many others, I became a fan of the show after it went into syndication -- it remains my favorite television SF series.
So here's today's trivia question: one of the main actors from Lost in Space and one from the original Star Trek appeared together as regulars in a later science fiction television series. Which one was it?
The answer is Babylon 5 (1994-98). Bill Mumy (danger, Will Robinson) appeared as a sort of acolyte for the main character from one of the alien races, while Walter (nuclear wessels) Koenig played a rather sinister telepath. The latter was a much more interesting role than Koenig's character on Star Trek. (And just where, exactly, did Koenig get his Russian accent? He was constantly pronouncing his v's as w's -- "wodka" instead of "vodka" -- while a real Russian would do just the opposite. And don't get me started on the name "Chekhov." When I later studied Russian literature, I could never take that particular writer seriously).
Babylon 5, unusually for television at the time, had a long-term story arc, although unlike many SF shows, the writers appear to have planned ahead and did not end up writing themselves into an unresolvable corner (see, e.g., Lost). The final resolution of the story arc seemed a bit too abrupt, and the last of the five seasons felt very much tacked-on (it was tacked-on -- there was doubt whether the show would be renewed for a final season), but all in all it's an excellent series -- my second-favorite SF television show.
Bonus: June Lockhart, who played Will Robinson's mother, also appeared in a single episode of Babylon 5. And there were several other shows employing actors from both Star Trek and Lost in Space. One was The Twilight Zone, which featured quite a few actors from both series, but then again, everyone and his brother appeared on that show. And another was Bonanza, which featured, at various times, Leonard Nimoy, James Doohan, and DeForest Kelley from Star Trek and the actors who portrayed Zachary Smith and Will Robinson's father from Lost in Space. Now that's just weird.