It's the bloodstained stiletto with a five-inch heel that became a gruesome weapon.
Then, straddling a life-sized dummy, another prosecutor showed the jury how he says each horrific blow landed on the victim's head and neck.
In pure courtroom drama, prosecutors showed how they say Ana Trujillo used the stiletto to stab her professor boyfriend 25 times. Prosecutor Sarah Mickelson took off her own high-heeled shoe and demontrated the fatal blows over and over again.
HLN host Nancy Grace told INSIDE EDITION, "He takes the shoe and begins beating the dummy, all the while explaining to the jury what occurred."
Fifty-nine-year-old Stefan Anderson, a University of Houston professor of biology, bled to death in his luxury high-rise. His death by stiletto is an echo of a scene in the 1992 movie Single White Female where Jennifer Jason Leigh's character killed a man with her stiletto.
Surveillance cameras show the couple returning home after a night out on the town drinking. Minutes later, Anderson was killed with the stiletto.
Defense attorney Jack Carroll claims Anderson attacked his girlfriend because she wanted to dump him and she used her blue suede platform stiletto to defend herself.
Carroll said, "He went off the deep end. She did what she had to do."
But Nancy Grace isn't buying the self defense claim. Grace said, "She hasn't got a scratch or a bruise on her body. Nothing! Nothing to suggest or support her theory there was a life and death struggle and she had to kill the victim with her only weapon, her stiletto heel."