Mork & Mindy was a spin-off from an episode of Happy Days
seen in February 1978, in which an alien from the planet
Ork landed on Earth and attempted to kidnap Richie.
So popular was the nutty character that Robin Williams
was given his own series the following fall.

Mork was a misfit on his own planet because of his
sense of humor. So the humorless Orkans sent him off
to study Earthlings, whose "crazy" customs they had
never been able to understand. Mork landed, in a giant
eggshell, near Boulder, Colorado. There he was
befriended by pretty Mindy McConnell, a clerk at a
music store run by her father, Frederick. Mork looked
human, but his strange mixture of Orkan and Earthling
customs such as wearing a suit, but putting it on
backwards, or sitting in a chair, but upside down,
led most people to think of him as just some kind
of a nut. Mindy knew where he came from, and helped
him adjust to Earth's strange ways. She also let him
stay in the attic of her apartment house, which
scandalized her conservative father, but
not her swinging grandmother, Cora.