Many of the Beatles' Saturday morning cartoons don't seem to have much overall sci-fi/horror themes in them. But most have at least one or two odd moments. Here is where we can post any of the miscellaneous things we see.
For instance in the Ticket to Ride cartoon, there is a moment where Ringo chases a girl through space and they end up on another planet where Ringo encounters his alien doppleganger. They both had the hobby of putting young women in cages.
However, that didn't seem to be the overall theme of the cartoon.
And in Elenor Rigby we see the old lady keeping a mask in a jar by the door, during the song when Paul sings that line.
However, the theme in the cartoon is about scaring little children into believing that witches are really just lonely people.
In It Won't Be Long, a scientist creates a potion that can shrink anything. He pours the potion into the lake. Later John falls in the lake and gets shrunk - then resized. Then later the other three fall in and get shrunk.
Maybe that's why Paul goes from 5'11" to 5'9" and back again over and over
(also interesting: in Help!, Paul gets shrunk by potion in a syringe).
And in Paperback Writer, there is a quick scene where George takes the other 3 into his lab to meet the robot he created. Which they end up accidentally destroying.
In Good Day, Sunshine their music controls the weather.
In I'm only sleeping it puts dragons to sleep. John also befriends Merlin the magician and King Arthur.
In Run For Your Life, Ringo gets bonked on the head by a statue while at a museum in Versailles, and imagines that John is Marie Antoinette. They kiss several times.
In Eight Days a Week, which aired Sept 10th, 1966, a girl grabs at Paul while he's driving, causing the steering wheel to come off and they drive off a pier.
In Long Tall Sally, John & Ringo put on cursed suits of armor and fight to the death. Until they accidentally set off the “Drums of Peace”.
In I Feel Fine, they go to Hollywood and Paul of all people spends the entire episode showing them how everything there is fake and phoney.
In I Call Your Name, they all sleep in the same bed, with a giant crystal over their heads? George plays left-handed
Greek Mythology in I Should’ve Known Better. Their music also destroys the Collesium in Rome.
Eight Frankenstein scenes that I've seen.
And of course there's the one from the Yellow Submarine film where John is a Frankenstein and he has to drink a special potion to become human.