The very opening sequence of The Good Nurse, set in 1996 in a Pennsylvania hospital, sees Eddie Redmayne’s character Charlie Cullen staring blankly as other nurses desperately attempt to revive a dying patient. As the camera closes in on Redmayne’s face, it’s a chilling moment in a film full of them. While his name may not be so familiar in the UK as it is in the US, Cullen remains one of America’s most notorious serial killers. When he was ultimately caught, he confirmed 29 murders – but experts believe the number could be closer to 400.

Based on Charles Graeber’s book The Good Nurse: A True Story of Medicine, Madness and Murder, the film shies away from being a portrait of Cullen – who was bullied mercilessly both as a child and during his time in the US Navy, and attempted suicide on several occasions. Rather, scriptwriter Krysty Wilson-Cairns (1917) concentrates on the endgame, as Cullen is finally caught after he takes up a role as a nurse in an Intensive Care Unit at Parkland Memorial in 2003.

Playing ‘detective’ is his close friend at the hospital Amy Loughren (Jessica Chastain), a single mother-of-two who initially bonds with Cullen when he first arrives. Like Amy, Cullen has two children, though his wife has taken them from him. He’s also sensitive to Amy’s health problems. She has a heart condition and no health insurance and fears she will lose her job if those at the hospital find out. Gradually, the seemingly harmless Cullen ingratiates himself with her and her family.

Things change when a 77-year-old woman dies suspiciously in the ICU after suffering an adverse reaction to her medications. But by the time two homicide detectives (Noah Emmerich, Nnamdi Asomugha) start investigating, the body has been cremated, leaving the trail cold. Amy is convinced Cullen has nothing to do with it, but further investigation suggests otherwise. Stranger still, the administrative staff refuse to talk, fearful of costly reprisals in the most litigious nation on Earth.

Directed by Tobias Lindholm, the Danish filmmaker who co-wrote the Oscar-winning Another Round (2020) and directed A Hijacking (2012) and A War (2015), The Good Nurse is a film that operates at a low temperature, simmering its ingredients until the final reel. For the most part, it doesn’t work like a Hollywood thriller, preferring a more realistic approach. But, still, there are some terrifying moments; at one point, Lindholm cunningly uses the sound of a heart monitor to register Amy’s mounting fear.