Simplify the following text for a Grade 9 native English-speaking person.
Original: In Earthshock ( 1982 ) , the actors ' chins were vaguely visible through a clear perspex area on the helmet to suggest some kind of organic matter .
Simplified: In Earthshock ( 1982 ) , the actors ' chins were vaguely visible through a clear perspex area on the helmet to suggest some kind of human face .