The billboard above Baltimore’s Pulaski Highway is hard to miss.

Inspired by the movie, “Three Billboards Outside Ebbing, Missouri,” Jenny Carrieri posted three billboards around the city to mark the 23rd anniversary this month of her twin sister’s murder.

Jody LeCornu was 23 when she was killed in a parking lot in Baltimore on March 2, 1996. The investigation is ongoing, and the killer is yet to be identified.

Jenny Carrieri, left, with her sister Jody Lecornu. NBC News

“I saw the movie, 'Three Billboards Outside Ebbing Missouri,' and I just thought it was brilliant. And I am constantly trying to figure out ways to share her story and find her killer,” Carrieri, 46, now of Easton, Maryland, told NBC’s Lester Holt.

Police confirm that after an evening at a local bar, LeCornu met a male suspect in the early morning hours in what is now known as the Drumcastle Government Center parking lot. At the time, it was a shopping center.

“The whole night was very out of character for her,” says her twin, who grew up with Jody LeCornu in Annapolis, Maryland. “She wouldn't have driven in the snow. I mean, she was terrified of everything. She was actually afraid to live in Baltimore. She would say she was afraid she was going to get shot.”

Jody Lecornu, left, and Jenny Carrieri. NBC News

Cpl. Shawn Vinson, spokesman for the Baltimore County Police department, tells NBC News, “There was some kind of exchange between the suspect and Jody in the parking lot to where she started to drive off. At that point a suspect pulled out a handgun, shot one time at her direction.”

Gravely wounded, LeCornu managed to drive across the parking lot into another shopping center across the street in Baltimore County, where she circled the parking lot before dying.

Vinson tells NBC News the suspect was “a black male, stocky build wearing a green Army fatigue-style jacket driving a white BMW.”

Police confirm that according to witnesses, the suspect followed her, drove into the shopping center, removed something from the car, and later drove away toward the Baltimore city area. Authorities have not been able determine what was taken from that car.

Jenny Carrieri posted a billboard in Baltimore last fall, then placed three more billboards around the city this month to mark the 23rd anniversary of her twin sister's murder. NBC News

“The key to this whole thing is what he wanted in that car,” Sheryl McCollum, a crime scene investigator, says. “When he gets to her in her car where she is clearly dying, he then reaches in to get whatever that is that is so important, before he flees.”

McCollum is also the director of the Cold Case Investigative Research Institute, a nonprofit organization that assists families and law enforcement with cold cases like LeCornu’s.

“You've got to talk to those witnesses. Maybe they told you everything, maybe they didn't. Maybe you haven't talked to everybody that knew something. That's why her billboard is so critical of this whole thing. I guarantee you people talked. Whoever was involved with this told somebody,” McCollum says.

The Baltimore County Police Department tells NBC News they have received phone calls but no substantial leads since the billboards have been up.

Vinson said the county police have never seen a family put up billboards in a case before.

The three billboards put up by Carrieri are in stark red, black and white, and feature an image of her sister under the words, "Find my killer." They offer a $100,000 reward.

Carrieri says she is not giving up and is already planning her next billboard. “I just feel part of me was ripped away. And the other part of me is going to find out what happened.”

After one billboard last fall, and now three more, Carrieri is hoping this apparently cold case will be hot once again. “I always said we were one. It's almost like I have her strength now, you know? She was always the strong one.”