Cindy Martin (Paula Marshall) is the villainess from "Flashdance with Death", episode 1.11 of Diagnosis Murder (airdate January 28, 1994). Cindy is a dance instructor and homicide detective Steve Sloan’s latest girlfriend.
The episode has Cindy being revealed as the killer of the co-owner of her dance studio by causing a short-circuit that fatally arrests his pacemaker. This was a revenge act for him breaking up with her, irrespective of the fact that she compromised her dancing career for their relationship. Now the investigating detective’s girlfriend, she skilfully sends Mark and Steve Sloan down the wrong track with several red herrings and false testimonies; other suspects get arrested on the basis of evidence fabricated by Cindy and she appears to get away with the perfect murder. Cindy additionally performs a lap dance for Sloan as he questioned her on her relationship with her victim, likely doing so in an attempt to distract him from the investigation.
Eventually, though, Cindy's attempts to evade Sloan's suspicions fail, and the villainess walks right into a trap set for her by the cunning doctor/investigator. Now unmasked as the murderer, Cindy breaks out in tears when Steve is about to arrest her. As she sobbingly swears that she never meant to kill anybody, Steve ignores her pleas and reads her rights to her. Cindy is led away to prison to face murder charges, and the wrongly accused are cleared.