Quicksand Fans

This is a request but its also off topic so I am placing it here, hoping some avid Perry Mason fan can provide the answer. I have a rather vague memory of a murder scene taking place in, as I remember it, either an episode of Perry Mason or one of the movies. I believe the scene actually takes place late in the episode but it was a very long time ago. The scene shows the victim of a murder by gunshot as she is killed. She stands, I believe in an apartment somewhere, and is quite calm and pleased as the murderer takes aim and fires. Then she collapses and dies. As I recall, the story was that she had hired the hit man herself in an attempt to frame someone else.

Can anyone provide info on the name of the episode or movie?

For what its worth, I think I finally identified the scene as from The Case of the Silenced Singer, a Perry Mason movie released in 1990.