The True Story Behind Netflix's 'The Good Nurse'

Not all heroes wear capes.

The Good Nurse chronicles the heroic, yet harrowing happenings of nurse Amy Loughren, who helped put an end to the killing spree of her colleague — and former friend — once she learned that he was responsible for the murders of dozens of patients over the course of sixteen years.

At the center of the story is Charles Cullen, who committed a series of crimes that took place in New Jersey and Pennsylvania.

The film, which is inspired by the 2014 Charles Graeber book The Good Nurse: A True Story of Medicine, Madness, and Murder, stars Jessica Chastain as Loughren, Eddie Redmayne as Cullen, Nnamdi Asomugha as Detective Danny Baldwin and Noah Emmerich as Det. Tim Braun.

"Watching the movie gave me permission to be proud of myself," Loughren told PEOPLE. "I showed up as a mom. I showed up as a nurse. I showed up as a friend. The only reason Charlie is not still murdering is because of my friendship with him."

Between the crimes Cullen committed and how Loughren helped put him behind bars, here's everything to know about the real-life events that The Good Nurse strives to tell.

Who is Amy Loughren?

Up until 2003, Loughren served as a nurse in the Intensive Care Unit at Somerset Hospital in New Jersey. She also worked as a trauma and ER nurse. During those years, the single mom of two described herself as an exhausted and overworked "lazy Buddhist," per her website.

It wasn't until 2003 that she was approached by two detectives suggesting that her coworker could be one of the most prolific serial killers in American history. After she helped expose the murderer, Loughren embarked on a spiritual journey in an attempt to cope with the trauma she faced in the wake of her disturbing experience.

She confided in spiritual gurus, energy healers, visionaries, and real-life and modern-day Buddhas to help her understand how she could have been friends with such a dark person. Upon finding the answers to her questions, she now guides others in finding deeper connections within themselves.

Per her website, Loughren currently works as a Reiki Master, a hypnotherapist, NLP practitioner, meditation instructor, DreamSculptor practitioner, reconnective healer, integrative energy healer, past life regressionist, crystal language reader and medical intuitive with over 30 years of experience.

Who is Charles Cullen?

Cullen was born on Feb. 22, 1960, and grew up in West Orange, New Jersey. In the wake of both his parents' deaths, he suffered from depression and attempted suicide numerous times, The New York Times reports. Prior to becoming a nurse, he served in the Navy for a short period of time, per The Good Nurse: A True Story of Medicine, Madness, and Murder.

Following his medical discharge in 1984, he enrolled as a student at Mountainside Hospital's nursing school in Montclair, New Jersey, where he was named president of his class. After he graduated in 1986, he landed a job in the burn unit at Saint Barnabas Medical Center in Livingston, New Jersey — the place of his first murder.

He married Adrianne Baum a year later and they welcomed two daughters together. The couple eventually divorced in 1993, according to official court documents obtained by The Morning Call. She also filed a restraining order against him due to domestic violence, per Warren County Family Court.

What crimes did Charles Cullen commit?

Curren worked as a nurse in hospitals across New Jersey and Pennsylvania — beginning his killing spree at Somerset Medical Center, the first hospital he was employed at in 1987. He killed patients by injecting their IV bags with lethal doses of insulin and heart medications.

He hopped from hospital to hospital, including Warren Hospital, Hunterdon Medical Center, Morristown Memorial Hospital, Lehigh Valley Hospital in Allentown, Pa. and St. Luke's. — despite being fired from or forced out of at least six facilities, according to NJ.com.

"Five hospitals knew he was hurting patients and still gave him a neutral reference, sending him on to continue his killing spree," wrote Loughren on her website.

Never miss a story — sign up for PEOPLE's free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human-interest stories.

How did Amy Loughren learn of Charles Cullen's crimes?

In 2003, Detective Danny Baldwin and Det. Tim Braun visited Somerset Medical Center to investigate abnormal lab reports after the deaths of several patients. Loughren was among the staff they interviewed and trusted with their gathered evidence.

Baldwin showed Loughren a record of the names and dosing information of drugs that her colleague Cullen had withdrawn while on duty in the ICU. "It was very, very obvious there was something not right," Loughren told PEOPLE.

She knew it was her duty to help with the case to prevent any more patients from getting hurt or killed, so the strong-minded nurse worked with the team of dedicated detectives and assistant prosecutors on the case.

How did Charles Cullen get caught?

After Loughren discovered the truth about Cullen, she agreed to secretly record conversations with him for Somerset County Police Department investigators. With police waiting outside, Loughren met him at a restaurant in an attempt to coax him into confessing his crimes.

Although she wanted to help put an end to the madness, she was morally conflicted because of her former friendship with Cullen. "I was wrestling with how much I still cared for him," Loughren told PEOPLE. "He was my friend. I didn't know the murderer."

Despite those thoughts, she confronted Cullen about the sudden deaths he had caused at the hospital. She even offered to accompany him to the police station to turn himself in.

Loughren told PEOPLE that his unsettling response still sticks with her. She recalled: "He sat straight up. The color of his eyes changed. He put a smirk on his face and said, 'I'm going to go down fighting.'"

What was Charles Cullen charged with?

Thanks to Loughren, who was able to get him to talk, Cullen was arrested and taken to the police station. Following his confession to the crimes he committed at the hospital, he was convicted of 29 murders and was sentenced to 11 consecutive life sentences in 2006.

Some experts believe that Cullen could be guilty of an estimated 400 murderers tied to suspicious circumstances in the deaths of patients at other hospitals where he worked in New Jersey and Pennsylvania, though the information can not be proven without further admission from Cullen.

Where is Charles Cullen now?

Currently, Cullen is serving a life sentence at New Jersey State Prison in Trenton as part of an agreement with prosecutors to help them identify his victims, per NJ.com.

The Good Nurse is currently showing in select theaters and premieres on Netflix on Oct. 26.