This was found at the superlative Pop Culture Safari.
For some reason its a musical tribute to the Batman TV show. If you weren't there, for some reason TV in the 1970's was full of lots of elaborate song and dance numbers. I blame Donny & Marie.
Its worth it to make it to the end to hear:
"up next: John Denver salutes Jacque Cousteau!"
there was something brilliantly weird about late 70's TV.