One would think the most interesting part of a book where the main character kills hundreds of people would be the murders. But you’d be wrong: It’s the cover-up.

Spurred by a Chicago Public Library challenge to read a true crime book, I checked out “The Good Nurse: A True Story of Medicine, Madness, and Murder” by Charles Graeber, soon to be coming to theaters near you.

The medical aspects of how nurse Charles Cullen killed patients is tragic and morbidly fascinating: The ordering of digoxin, the spiking of IV bags with insulin, systemic flaws related to canceled orders. But it’s the healthcare system’s desire to make the problem go away without taking responsibility that will strike fear in your heart.

Cullen spent 16 years working in different hospitals and a nursing home in the Pennsylvania and New Jersey corridor. He arrived at the nursing home, then called Liberty Nursing and Rehabilitation Center of Allentown, through a staffing agency. His previous hospital, which had fired him for “incompetence, patient complaints and grave medication errors, simply confirmed his former employment.”

“Nobody at Liberty questioned why a nurse with ten years of hospital experience would downshift to a nursing home and a $5-an-hour pay cut,” Graeber writes.

To be fair to his many employers, Cullen was the type of nurse everyone loved at first: Willing to take weekend, holiday or night shifts, efficient and, as the years went on, experienced. “His fellow nurses considered him a gift from the scheduling gods, a hire almost too good to be true,” Graber writes.

Eventually, people started paying attention to the rise of unexplained deaths around them. When Cullen loaded a syringe with insulin and put it directly into a patient’s IV at Liberty, causing his death, he expected questions. But the nursing facility fired a senior nurse, who hit back with a wrongful termination suit. The suit was settled out of court, with the nurse signing a nondisclosure agreement. A few months later, Cullen was fired. But a staffing agency found him more nursing work within days.

While that section of the book will make you cringe, wait until you hit the parts where the hospital executives tells the police there aren’t records past 30 days for its Pyxis MedStation 2000 or Cerner, which had its patient charts. The risk manager of the hospital matter-of-factly tells investigators that Pyxis stores records only for 30 days. The investigator, on a whim, calls Cardinal Health, which makes the system. A sales rep is confused when the police officer says he’s looking for older data and asks if there’s “any way to recover anything that far back.” The rep tells him there is no 30-day window, and that Pyxis stores every piece of data.

“Just pull it up,” he said. “Is there something wrong with your machine?”

As scary as the book is, as healthcare professionals, we know Charles Cullen is an anomaly. After all, a fellow nurse is ultimately the one who was able to get Cullen to confess. While some others would occasionally reach out, such as with a call to Poison Control or others who threatened to quit if Cullen were hired, there are dozens of people in the book who chose to look the other way. Or, in the case of certain hospital executives, lie deliberately. It’s hard to know what’s going through their minds: Misguided loyalty to the hospital, fear of scandal, or the sense that it would be more trouble than it was worth to pursue Cullen?

Specific laws stemmed from the Cullen case, such as New Jersey’s 2004 Patient Safety Act, which increased hospitals’ responsibility for reporting adverse events, and a later law that said complaints and disciplinary records relating to patient care must be kept for at least seven years.

Ultimately, what I came away with is that we need to create healthcare environments where direct care staff who notice suspicious behavior are allowed to speak up. We need better medication tracking systems. We should read books such as “The Good Nurse” to learn how Cullen escaped notice for so many years. And finally, if the police come knocking at your door, it’s in your best interest to cooperate. Not just because you’ll be caught if you lie — and you will get caught — but because at the point where you’re casual about patient lives, it’s time to choose another profession.

Follow Senior Editor Elizabeth Newman @TigerELN.