Spasmo (1974)

Synopsis:
This giallo from the infamous Italian director Umberto Lenzi begins as Christian goes for a romantic stroll on the beach with his girlfriend. During the walk, the two discover what they first believe to be a dead body, but, upon closer inspection, find that the woman is still alive. Things take a turn for the worse afterward when, days later, Christian meets the woman he saw laying on the beach at a yacht party and begins an affair with her that plunges him into a bizarre mystery and even makes him a murderer.
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