The Ending Of The Good Nurse Explained

"The Good Nurse," which is now streaming on Netflix, is both another dose of the ongoing true crime trend and, in its own subtle ways, an antidote to it. The film is based on real-world events covered in the 2013 book, "The Good Nurse: a True Story of Medicine, Madness, and Murder" by Charles Graeber." The tale the book tells is of one of the world's most prolific serial killers, so audiences can understand why filmmakers were eager to bring it to life on screen. However, "The Good Nurse" avoids most of the tropes of the ever-popular genre. The body count is high, but the level of mystery, gratuitous violence, and amateur psychologizing are quite low. Instead, this thoughtful — but still tense — film chooses to focus on the struggle and the bravery of the woman who brought him to justice as well as the culpability of America's health care system. 

There's never really much doubt about the identity of the killer. "The Good Nurse" signals to us in the pre-credits sequence that it's Charlie Cullen, played by an understated yet off-putting Eddie Redmayne. His fellow nurse and fast friend is Amy Loughren, stoically but gently portrayed by Jessica Chastain. The case against Charlie is pretty cut and dry in hindsight, so the drama comes entirely from waiting for Amy, our point-of-view character, to discover the awful truth. Along the way, the film — which takes place over five months — makes references to the book's more thorough 16 years of reporting. This is how Charlie's killing spree finally came to an end and where it leaves its hero and his victims. 

We might suspect Charlie is a creep and a killer early on, but Amy's just happy to have help and a friend. The health care system is painted as one of the villains in "The Good Nurse" not just because it was complicit in covering up Charlie's crimes, but also because American for-profit medicine means corners get cut and a nurse can't afford coverage. The film shows Amy bending the rules for the greater good. She's admonished for letting Mr. Martinez sleep in a chair so that he can stay with his scared wife, Ana, overnight, and she's also attempting to keep the Martinez's insurance from ripping them off. Amy's also hiding her own serious condition, cardiomyopathy, so she won't lose her job before her insurance and paid leave kick in.  

This single mom is hanging on by a shoestring. She struggles to pay the babysitter her kids don't like, and every time she gets stressed (which is always), she's at risk of a stroke. Charlie inserts himself into Amy's life by becoming her support system. He rehearses lines for the school play with her older daughter, Alex. He tends to patients when she needs a break. He takes her to her cardiology appointments. Crucially, while Amy will bend the rules, she won't break them. But Charlie will, for her. When her heart rate goes too high, he uses a flaw in the computer system to steal the medication she needs. Though Charlie is about to start killing again, he also finds purpose in (and one could argue, becomes obsessed with) taking care of Amy. He earns her trust, in part because of his fixation on her and in part to protect himself. 

Amy is extremely welcoming and friendly when she first meets Charlie. She lets her professional guard down quickly, sharing details about her personal life and bringing him home to meet her kids. Still, as she spend more time with her colleague and new best bud, she seems to clock some things from his past that just don't sound right. Though they're filtered through the perspective of someone who sees himself as the victim, all of Charlie's odd statements are, in retrospect, clear proof that he's an abuser. 

In one of their first heart-to-heart conversations, he complains to Amy that his ex-wife moved six hours away and that she's constantly finding excuses not to let him see his girls. On one occasion, he vents exasperatedly about how she's making up stories in which he was "mean" to her dog. Later, that story evolves and he claims she's accusing him of poisoning the dog. Even the way Charlie knows how to game the PYXIS system by canceling prescription drug orders just before the drawer opens sets off an alarm in her head, though she's not in a position to refuse the meds when they're for her. Though they'd gotten incredibly close, Charlie's behavior was noteworthy enough that when detectives approach her a second time about her fellow nurse and warn that he might not be who he says he is, she's at least able to entertain their suspicions. 

Thankfully, Amy remembers that she and Charlie have a mutual acquaintance: Lori Lucas. Amy meets Lori for drinks and after exchanging some pleasantries, she says she wants to talk about something "weird." She asks if Lori remembers Charlie Cullen, and the mood changes. "There was a rumor about him, that he was responsible for a death," Lori says in a tone of voice that's half afraid and half gossipy. Her story matches up exactly with what Amy has experienced. He was suspected of purposefully overdosing someone by pin-pricking a saline bag and contaminating it with insulin. More contaminated bags were discovered, but Lori says no one thought to blame Charlie until he left. While he was in her wing, there'd be emergencies every night, but once he was gone, there'd only be one a month. 

Amy rushes back to Parkfield and inspects the saline bags. Sure enough, one has been tampered with. Fluid leaks from a pinprick. This is the point of no return as far as Amy is concerned. She's utterly convinced that Charlie is responsible. Not only does she begin actively cooperating with the investigation, but she also watches out for patients in the ICU by switching their saline bags after Charlie's done his rounds. Amy's night out with Lori is an important step in solving the case, but it also shows how he was able to get away with murder for so long. His actions were an open secret, but everyone — including Lori — chose not to involve themselves for fear of him and of losing their jobs. 

Because Charlie's canceled prescription orders aren't the smoking gun she hoped they'd be, the detectives enlist Amy to elicit a confession. First, they record a phone call between her and Charlie. He wants to meet her at the park with her kids, but Baldwin directs her to invite him to lunch. We can tell they've hooked her up to a wire when she communicates with Braun and Baldwin from her booth in a diner as she waits for Charlie to arrive. They can hear her dangerously rapid heartbeat, and her quiet curses give away how petrified she really is. 

He walks in casually and attempts some small talk, but Amy is anxious to get to the point. At first, she tries to seem loyal and goes on about how everyone is badmouthing him and probably badmouthing her, too. She tells him she stood up for him, but he says he doesn't want to talk about Parkfield. Amy presses the issue with a kind of intimacy designed to encourage him to talk. She says she could understand why he might do those things. The implication here is that he may have been conducting mercy killings. Though Amy doesn't believe this, it's a tactic to get him to confess. But it doesn't work. Charlie's reaction is the first of two indications of the extent of his violence and madness. He lashes out by slamming his hand on the table. Immediately after this outburst, he calmly tells Amy about his new custody agreement. She tries once more, but he leaves for his new job as if nothing unusual has happened. 

"The Good Nurse" doesn't delve too deeply into the reasons Charles Cullen may have committed serial killings in such an anonymous, unusual way, but there are allusions to the book throughout that provide some insight. When Ana dies, Charlie offers to prepare the naked body while Amy goes off to talk to her husband. A difficult-to-watch sequence follows in which he takes too much pleasure in the idea that he's ended this woman's life. But prior to being left alone with Mrs. Martinez, Charlie tells Amy about a painful detail from his past. His father died when he was a baby, then his mother was killed in a car accident when he was a young teenager. The hospital lost the body for awhile, and once he was allowed to see her, he says she was uncovered, naked, and a "total mess." Charlie laments that's how he remembered her for the longest time. 

Charlie also talks disparagingly about his ex-wife and former co-workers on several occasions. When Detective Braun is attempting to secure a confession, he asks Charlie if his victims were all women and if he did this because of his mother or ex-wife. The movie touches on his lifelong fascination with poison by bringing up the dog, but it doesn't tell the full story of the extent of Charlie's mental illness or criminal past. The serial killer who would come to be known as the Angel of Death dealt with depression and alcoholism and attempted suicide with substances on more than one occasion. He felt isolated from his family and peers and demonstrated a propensity to harm others, too, from a young age. 

If you or anyone you know is having suicidal thoughts, please call the National Suicide Prevention Lifeline by dialing 988 or by calling 1-800-273-TALK (8255)​.

If you or anyone you know is struggling with addiction issues, help is available. Visit the Substance Abuse and Mental Health Services Administration website or contact SAMHSA's National Helpline at 1-800-662-HELP (4357).