In the Heat of the Night (1988)

S5E17 By Means Most Foul

A restaurant owner and her boyfriend, who works as a mechanic, devise a plan to get rid of her husband, but their plot takes an unexpected turn. Meanwhile, Gillespie faces scrutiny for a series of mailbox vandalism incidents. Virgil quickly realizes his mistake in dismissing Parker's prediction about the vandals' next target, leading to unforeseen consequences.