At one point both Big Zapper films were on youtube, loved the first one but found the second not as entertaining and a bit dull.
Don't think i've seen any of the others.
Doh.. Actually looking back i've got night after night, a good and grimy sleazy British slasher.
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MIKE: I've got it! Peter Cushing! We've got to drive a stake through his heart!
VYVYAN: Great! I'll get the car!
NEIL: I'll get a cushion.