Dylan McDermott helped solved his own mother's murder, and no, this is not the plot of a new movie.

When he was just five years old, McDermott was (sort of) witness to his mother, Diane's, death. After years without justice, McDermott knew he had to take things into his own hands.

Childhood

Dylan McDermott was born Mark Anthony McDermott on October 26, 1961. Diane was just 15 years old when she have birth to her son, and Richard McDermott (his father), was only 17. Richard earned money for the family by hustling pool, even after he and Diane separated.

Diane started seeing a new man when Dylan was young, by the name of John Sponza. Sponza was a known gangster and heroin addict, but Diane still moved Dylan and his sister, Robin, into the home.

Mom's Death

Sponza was a well-documented violent man, who was no stranger to taking his aggression out on Diane and Dylan. It was not unusual for him to throw Dylan to the curb for the night, which is exactly what happened the night of Diane's death.

Dylan was left outside in the freezing cold temperatures when he heard shouting and then a gunshot. The next thing he knew, his mom was being whisked away in an ambulance with a gunshot wound to the head. Sponza told police that Diane shot herself in the head by accident while picking up a gun that Sponza was cleaning. Almost immediately after, Sponza changed his story to say that Diane killed herself.

Police took the story of suicide as fact, and the case was closed on Diane McDermott's death.

Mom's Murder?

Forty-four years after his mother's death, something wasn't sitting right with Dylan McDermott. He believed there was more to the story of her suicide, and approached the Waterbury Police Department to ask them to re-open the investigation.

As Superintendent Michael Gugliotti, Detective Richard Baxter and Lieutenant Gary Pelosi began to look into Diane's death, they realized things weren't adding up. Medical examiner H. Wayne Carver noted that the gun found near Diane's body was too small to be the one that killed her. He also noted that the murder wear had been pressed to the back of her head, which is not possible with suicide.

"What troubled me was that there was very little follow up other than the statement Sponza had given to police," Gugliotti said. "Sponza is telling the police that night that he very rarely, if ever, had arguments, yet every we spoke to, including Dylan, who was only 5 at the time, remembered very violent, vicious arguments... Dylan vividly recalls the amount of times, not only flashing the gun, but pointing it at the kid, saying, "˜Shut up and get out of here.' He's still probably traumatized by that."

After more digging and investigation, Dylan McDermott's gut-feeling was validated: his mother was murdered.

"I'm happy to know my mother wasn't mentally ill or depressed," said McDermott's sister, Robin Herrera. "Somebody took her from us; she didn't leave us."

The new investigation concluded that not only was Sponza responsible for Diane's death, but he was also involved in two other unsolved homicides. However, justice was not going to be served through the court system.

Sponza's Justice

After it was revealed that Sponza wasn't, in fact, the kind-hearted man he told police he was, they began to uncover his ties to organized crime and violent past. According to police, the only reason Sponza's story wasn't pulled apart at the time of Diane's death was that his father ran the local prison. There are also theories that he was a police informant, and the detective working the case at the time didn't want to jeopardize their relationship. That detective was mysteriously fired years after the murder.

But the old adage of "what goes around, comes around" stood true in the case of Sponza. In 1972, five years after Diane's murder, the gangster was found dead in the trunk of a car, parked outside a grocery store. It's believed his death was due to his ties to gangs and organized crime.

Life After Mom's Death

After Diane was killed, Dylan learned to bury it deep down.

"He said, 'In order for me to survive and to get where I am today, I needed to bury that moment in my life deep within myself,'" Gugliotti revealed. "He said, 'It wasn't until recently that I've come to the point in my life where I'm able to begin to process all of this and make it part of [my] life.'"

Dylan and his sister were taken in by their maternal grandmother after their mother was killed, trying to live as normal a life as possible.

When he was 15 years old, Dylan's dad met and married Eve Ensler, who ended up adopting Dylan. She encouraged him to follow his acting dreams, and the two remain close to this day. Dylan's bond with his step-mother is so close, that she is the reason he changed his name from Mark to Dylan. Ensler suffered a miscarriage, and said she would have named that child Dylan, which is what prompted the actor to make this his legal name.

The Golden Globe winner surely has dealt with a lot in his life, but we are glad he was able to honor his mother's legacy by finding her killer.