When I was a kid, more than 30 years ago, I remember watching a TV show at school in the UK. Would have been mid-to-late '80s. I think it was probably part of an English language thing, where they'd have worksheets for the kids to do after watching the show.
In this TV show, there were aliens who masqueraded as humans. Sometimes they'd revert to their alien form and I think they were bald, and definitely had no noses. I remember the poor cast members were wearing prosthetics that blocked their ability to breathe normally, and ended up delivering their dialogue sounding terribly nasal.