I remember seeing a promo for what seemed to be a made-for-TV movie from the mid â€˜70s. It was probably CBS or NBC. The plot involved an older couple who were caring for a grandchild or adopted child.
One of them (probably the man) was secretly poisoning the child, and the other one began to suspect. There was a particularly shocking shot of a woman, in an apartment at night, with her hair on fire. She was screaming, not trying to put it out, just screaming and burning. I remember scrambling to the T.V. to shut it off immediately. I was haunted for months. I never knew what movie or show it was.
I don’t think that this is the answer, but I wanted to throw this out. Mid 70s woman screaming with her hair on fire points in one direction for me – 1975’s Bug. Here’s the scene – and CBS did use a cut of the money shot in promos for it when they ran it on late night Fridays…