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Who Was Amanda Plasse & What Happened to Her? 2026 Update & Profile

Ryan Gill

Amanda Plasse was a 20-year-old woman from Chicopee, Massachusetts, known for her lively personality, artistic flair, and deep love for those around her. Petite in stature—standing just over five feet tall—she had a presence that lit up a room. With her curly brown hair, expressive tattoos, and passion for journaling and drawing, Amanda embraced life in her own colorful way. Friends and family described her as free-spirited, outspoken, and loving. She worked as a waitress at Friendly’s, where she was well-liked by both coworkers and customers.

Amanda lived independently in a third-floor apartment on School Street. Her world was small but full—family, close friends, new romantic interests, and dreams still unfolding. Her mother, Michelle Penna (formerly Mathieson), remained deeply involved in her life, and Amanda was known to keep in regular contact. She had recently begun seeing a man named Seth Green, a carpenter, and things seemed to be looking up.

The Day Everything Changed

On August 26, 2011, Amanda’s promising future came to a horrifying end. That afternoon, after failing to show up for work, Amanda was found dead in her kitchen by Seth Green. She had been stabbed multiple times and her throat had been slit. The crime scene was chaotic—bloody footprints, smears on cabinets, and signs of a struggle pointed to a violent and personal attack. Amanda had fought for her life.

Initial suspicions focused on those closest to her, but DNA and forensic evidence ruled them out. A palm print, blood evidence, and a size 7½ men’s sneaker print were collected, but the investigation hit a wall. Months passed with no arrest. Her mother refused to let the case fade. She organized road races in Amanda’s memory, distributed flyers, and pushed police to keep searching for answers.

A Hidden Clue and a Breakthrough

Sixteen months later, investigators took another look at the case from scratch. While reviewing photographs of Amanda’s apartment, detectives noticed something they had previously missed: a whiteboard in her bedroom with the words “Dennis was here 8/11/11.” The date was just two weeks before her murder. The name Dennis had not appeared in any previous leads.

After tracking down nearby residents named Dennis and comparing numbers to Amanda’s phone records, detectives identified a man named Dennis Rosa-Roman. He lived just a few blocks away. He denied knowing Amanda or ever being in her apartment. But when shown the whiteboard photo, he admitted to writing the message—contradicting his earlier statements. DNA under Amanda’s fingernails confirmed the match. Rosa-Roman was arrested in 2013 and later convicted in 2016 of first-degree murder. He was sentenced to life in prison without parole.

The Aftermath and Legacy

Amanda’s murder left a permanent void in her family’s life. Her mother, who had fought tirelessly for justice, believed that the trial and sentencing brought some closure—until 2025, when she was informed that Rosa-Roman would become eligible for parole in 2028 due to a new legal ruling regarding sentencing of young adult offenders. The ruling has reopened old wounds and reignited the family’s fight to ensure Amanda’s killer remains behind bars.

Amanda Plasse is remembered not just for the tragic way she died, but for how she lived. She was a daughter, a sister, a friend, and a young woman with hopes and creativity. Her case mobilized a community, tested the resolve of a grieving mother, and continues to raise important questions about justice, memory, and the rights of victims’ families.

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