8. The Wadsworth Family - The Baby
Released in 1973, Ted Post's The Baby is one seriously messed up movie. As for the messed up family at the centre of this tale, that would be the Wadsworths.
Known only as Baby, the focal point of this feature is a 21-year-old man (David Manzy) who is believed to be mentally impaired. Ruth Roman's Mrs. Wadsworth has been fiercely protective of her son ever since his father left shortly after his birth, and she and her two daughters spend their days and nights caring for Baby.
With the capacity of a toddler, Baby comes under the spotlight of social worker Ann Gentry (Anjanette Comer). Upon delving deeper into this case, Ann realises that Baby doesn't have any physical or mental conditions - he has instead spent all of his life being beaten or shocked with a cattle prod any time he's attempted to do anything remotely non-baby-like.
The three Wadsworth women had used poor Baby and his purported disabilities to maintain a strong paycheck coming into the household. When Ann removes Baby from the Wadsworth house, the trio seek out to murder Gentry... in a plan that goes spectacularly wrong.
Attacked in her own home, Ann - with assistance from her mother-in-law - kills Germaine and Alba Wadsworth, before burying their mother alive next to their corpses.
In one final kicker, though, it's revealed that Ann wanted Baby for herself, so that he can be a playmate for her husband - who had been left with the mental capacity of an infant after a car accident.