The prologue featuring the two talking wigs was shot late in post production to pad out the film so it could have a feature length running time (over 70 minutes). Filmed in Miami, Florida.
H.G. Lewis loves to stage bloody set pieces There his bread and butter) and these films made him a pile of money because they're cheap to produce and they made grea drive-in fair. However in order to show them off he likes to make a feature length film. Many of them aren't very good and they're padded out to make the 70 minute mark. The Gruesome Twosome is one of those films.
The film revolves around a crazy old lady who makes nice realistic looking wigs and her ogreish son. She has a secret in her wig making that you'll find hair raising. They're many filler scenes placed through out the movie. The most notorious one (and clever) takes place in the beginning where two wigs are holding a conversation. The gore set pieces are cool but you'll have to sit through the movie to experience them.