The first season is
sooooooooo very different -- B&W (as the 1965/66 season was the last year an American primetime show could be broadcast in B&W) and more-or-less legit sci-fi for television. After that, as everyone seems to recognize, the show dropped into garish color camp-shlock with the robot ("Warning... warning... aliens approaching!!) and that special-guest-star queen ("Ohhhhh, the pain, the pain...!") at the center, all apocalyptically underscored rather niftily by a young "Johnny" Williams (who uses lots of bells to convey looming catastrophe).
Guy Williams always looks to me a little like JFK (obviously resurrected to continue his series TV career), June Lockhart (isn't she still alive today, at 126??) and Billy Mumy proves yet again that
Moon in Capricorns make the best child actors (when they're not the worst, simpering like Shalane McCall -- which explains Victoria's shift from simpering crap actress to excellent actress circa 1982, and a birth certificate perpetually rolling forward to make her "twelve" when DALLAS started).