Jessica Chastain: The Good Nurse was nerve-wracking

Jessica Chastain says 'The Good Nurse' was the most "nerve-wracking" film of her career.

The Oscar-winning actress plays the nurse Amy Loughren – who helped take down her serial killer colleague Charles Cullen (Eddie Redmayne) – in the new Netflix movie and explained the unique pressure of having the real-life Loughren observing her performance.

Speaking to IndieWire, Jessica said: "It was different than anything else that I have ever done because I have never filmed a scene from someone's life as they observed me acting it.

"She was at the monitor. That was a very nerve-inducing, nerve-wracking thing to do. It's a great responsibility anytime you play someone's story, but especially while they're watching you do it."

The 47-year-old star praised Loughren for being so "generous" as she helped craft scenes for the movie.

Jessica said: "She was like an angel."

The film has been directed by Tobias Lindholm and is adapted from Charles Graeber's 2013 book of the same name and the filmmaker praised screenwriter Krysty Wilson-Cairns for telling the story so vividly.

He said: "When I read the screenplay for the first time... (it) reminded me of my mom in the case it was a portrayal of a struggling single mom who took down the most prolific serial killer in American history with the help of kindness. That was her superpower.

"And that reminded me of all the hardworking moms out there, the unsung heroes that we never tell about, so that was my way in, celebrating Amy and her heroism."

Lindholm explained that it was a "big challenge" to avoid falling into the typical structure of serial killer films.

The Danish director said: "There are so many clichés in this genre, so to be able to find new ways and find more realistic ways to approach this was the aim.

"But it's hard because I'm a slave of the conventions as anybody. So we had to confront that, which was probably why it took so long."