Gayle Hunnicutt (born 1943, USA) and David Hemmings (1941 – 2003) in Fragment of Fear (1970); Playing Hemming’s love interest is his real-life wife, the gorgeous Gayle Hunnicutt, who apparently got the role as a condition to securing Hemmings’ involvement in the project (Kult Guy’s Keep)
24 Femmes Per Second 
The man is David Hemmings and the film is “Fragment of Fear” made in 1970. No idea who the girl is though,
Thank you.
She is Gayle Hunnicutt, co-star in the film and Hemming’s wife at the time. Again, many thanks for soling the mystery of the movie in the first place.