What does this tagline even mean?

While searching for showbiz anniversaries on this day, I came across the Tony Randall / Janet Leigh movie Hello, Down There which was released 50 years ago on this very day. But the tagline threw off the rest of my research so it's the only "today in showbiz history" factoid you get this morning. 

A combo of scuba dupes rock up a storm in a mad pad under the surf!

WHAT DOES THAT EVEN MEAN? Is it in English? I recognize the individual words but can't comprehend their meaning as a sentence. Was it a mad-libs of  common late '60s vernacular?

If you've seen this movie or even if you haven't and would like to try, please decipher for us.