From The Perry Mason TV Show Book
Politician Jason Foster is running against Randolph Cartwell for a state senate seat, but it doesn't look to be a clean race. Foster's rebellious sister Susan has been secretly dating David Cartwell, the son of Jason's opponent. Little does she know she's being used as a pawn in a dirty tricks campaign by Harry Mardig, a political boss.
When David Cartwell turns up dead, Jason's wife Margaret is accused of the crime. Perry comes to the rescue, but he finds his client is not being very helpful. The reason: She believes her husband may have committed the crime.