King kong / Tom Of T.H.U.M.B. was a JApanese production even though Rankin
BAss and Videocraft International claimed credit for it. Most of the Rankin BAss
stuff was produced by their 
ANI-MAGIC company actually in Japan. It worked
out cheaper and the end result was better anyway.
The half hour colour cartoon series was produced in 1966 and consisted of 2 episodes of
King Kong separated by one Tom Of T.H.U.M.B.
King Kong followed the adventures of Professor Bond and his son Bobby, daughter Susan and
King Kong a 50 feet Gorilla, ten times as big as a man. The stories were based on
Mondo Island in a
prehistoric jungle with dinosaurs and other prehistoric animals and
evil villains who wanted to capture and exploit King Kong or exploit 
the
Islands resources for evil purposes. CAptain Englehorn, a ships captain regularly
visited the Island and always smoked a pipe.
Tom was an average member of the U.S. Intelligence Maintenance
Department. He was sweeping the floor when he fell down the stairs and
whilst being helped by his faithful assistant Swinging Jack, an oriental Martial Arts
expert, accidently turned on the shrinking lazer beam ray gun and both were miniatureised.
They gave their height to their Country, creating the Tiny Human Underground
Military Bureau (T.H.U.M.B.)
Tom's
office and home was a filing cabinet. The Chief used him when regular sized
men were too big for a job. 
The main enemy was MAD - Maladjusted Antisocial and Darn Mean, an organisation of
Scientists trying to destroy the world for their own means.