Nightmare

Nightmare is a 1981 American psychological slasher film written and directed by Romano Scavolini, and starring Baird Stafford and Sharon Smith. Its plot follows a deranged man who, after undergoing an experimental medical procedure, is released from a New York City psychiatric hospital and embarks on a road trip to Florida with the intent of murdering his ex-wife and child.

Synopsis from Wikipedia, CC BY-SA 4.0. Everything below written here.

Poster © the film's rights holders.