Madhouse aka There Was a Little Girl (1981) 

$8.15

Julia, a teacher in a school for the deaf, has a hideosly disformed and deranged twin sister that resides in the local looney bin. She escapes to gate-crash a surprise birthday party for Julia by murdering all the party guests with the help of a giant killer Alsation dog, which gets it's come-uppance when lobotomised by a power drill, in a scene that will offend most animal lovers. - IMDb

 

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