'The Avengers' (1961-69)
 Like many series of the '60s, British import "The Avengers" combined sci-fi with another genre -- in this case, the spy thriller. The increasingly surreal and fantastical series revolved around dapper secret agent John Steed (Patrick Macnee) and a series of primarily female cohorts (American audiences best remember Diana Rigg as the coolly sexy Emma Peel) as they battled mad scientists and other evil enemies usually planning to conquer the world. A 1998 film version was an outright disaster.

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'The Outer Limits' (1963-65)
An anthology like "The Twilight Zone," "The Outer Limits" was
more straight science fiction than Rod Serling's fantasy potpourri.
But creator Leslie Stevens and producer Joseph Stefano (who
wrote the screenplay for "Psycho") filmed their tales like gothic
horror stories, making every scientific installation into a haunted
house and every rubber alien into a bizarre metaphor for the
characters' fears. The result was some of the most innovative
genre television of its time. Although the special effects often let
the show down, "The Outer Limits" provided some memorable monsters -- and more than a few goosebumps.

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'Voyage to the Bottom of the Sea' (1964-68)
 Described once as "'Star Trek' underwater," "Voyage to the Bottom of the Sea" was the first successful sci-fi TV series from producer Irwin Allen (the man behind later disaster epics such as "The Towering Inferno" and "The Poseidon Adventure"), but lacked "Star Trek's" intelligent approach. Episodes like "The Price of Doom" featured menaces like a giant clump of plankton that expanded throughout the show's advanced submarine, the "Seaview." Through four seasons of battles with thinly disguised Cold War enemies, undersea monsters and alien invaders, "Voyage" was mostly just waterlogged. 

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'Lost in Space' (1965-68)
Many of us watched Irwin Allen's second sci-fi series, "Lost In Space," as children, caught up in the plight of the Robinson family, their faithful robot servant and troublemaking stowaway Dr. Smith (Jonathan Harris) as they wandered deep space in search of Earth. But looking back with (sigh) adult eyes, one realizes that the acting was borderline campy and the plots were formulaic to say the least, usually revolving around Smith causing some sort of havoc with his greed and stupidity. Mixing sci-fi, family adventure and comedy, "Lost In Space" never really found its way.

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