Forbidden Zone
(1980)

The Queen (Susan Tyrrell) and the Ex-Queen (Viva) battle it out after Renee Henderson (Matthew Bright) kills herself/himself by jumping into a cage of horny men.  The Queen kills the Ex-Queen.  King Fausto (Herve Villechaize), Flash (Phil Gordon) and Gramps (Hyman Diamond) all show up to prevent the Queen from murdering Frenchy (Marie-Pascale Elfman).
 
Meanwhile Satan (Danny Elfman) has captured the Princess (Gisele Lindley) and cut off Squeeze-It Henderson's (Toshiro Boloney) Head.
 
Flash is accidentally killed by Gramps.  Ma Hercules (Viginia Rose) arrives and shoots the Queen.  Frenchy is made the new Queen and the Hercules family has made peace with the 6th Dimension as they all now plan to take over the world.

Thanks Atom12!