The car Jessica Walter drives is a Jensen Interceptor convertible. They were hand-built in England from 1966-76 using Chrysler engines and transmissions. The convertibles were made only in 1974 and '75, with a total production of only 267.
In the 1970 Barbi Benton was mostly known for posing in Playboy and being Hugh Hefner's girl friend for several years. With Hefner's help she became a music recording artist. Her rendition of "Ain't That Just The Way", which is heard here, was a middling success on the American charts, but a much bigger hit in Europe, and reached #1 in Scandinavia after it was released.