I don't remember the first season of Lost in Space (1965-68), when the family of colonists -- waylaid en route to Alpha Centauri was having realistic science fiction adventures. I only remember the last two seasons, where they were mostly crashed on a studio backlot, wandering around in bright pink and lavender jumpsuits, and encountering:
A lonely boy from the other side of the looking-glass
An intergalactic zookeeper who wants them as specimens
The contestants in a Miss Galaxy pageant
A giant talking carrot
It wasn't exactly Star Trek -- well, the Star Trek episode with the space hippies was almost as bad -- but it was fun. What kid in the 1960s didn't want to be lost in space with the Robinsons?
Billy Mumy, a busy child star with previous roles on The Twilight Zone and Village of the Giants (and later on Bless the Beasts and Children). Not only because he was cute, and knew it, getting teen idol attention at the age of twelve -- but because his character, Will Robinson, was bright and resourceful, a respected crew member, never told "you're just a kid" or "wait here where it's safe."
And Dr. Smith (Jonathan Harris), an accidental stowaway who provided comic relief. He was a big kid, an unrestrained id, gluttonous, lazy, cowardly, incompetent -- and flamboyantly feminine. The unabashed friendship between a young boy and an older man assumed to be gay was quite progressive in an era where gay men were often accused of being pedophiles.
Tommy Kirk). Since the spaceship was crashed through most of the
series, he didn't have a lot to do, and we didn't find out much about
him except that he was dreamy, and not interested in girls. In early
episodes, he had a romantic involvement with the older Robinson
daughter, Judy (Marta Kristen), but soon it was dropped and forgotten
Unfortunately, the female crewmembers had even less to do than Don
West. Maureen was a respected biochemist, but she was relegated to
cooking and saying "Be careful." Judy helped her mother cook. The
youngest daughter, Penny (Angela Cartwright, previously of Make Room for Daddy), had a few adventures, mostly involving adopting weird alien animals.
Kurt Russell guest stars as an alien warrior. There was an occasional shot of a muscular alien. But the main draw for gay kids was the boy adventurer and his flamboyant pal.