Caitriona Balfe says it was "really inspiring" to see Rami Malek's "meticulous attention to detail" in 'The Amateur'

She told Extra: "It's just that kind of meticulous attention to detail and also that passion, it was so evident, and it was really inspiring.

"And he's just also, he's just, like, the sweetest, kindest human... with the best mom. I love his mom."

Speaking alongside their co-star Rachel Brosnahan, she agreed when the 34-year-old actress hailed him as a "dream" and a "generous partner on and off-screen".

Rachel said: "He's just a dream. He's such a generous partner on- and off-screen. He had such a heavy workload ...

"He just can make you feel like you're the only person in the room, and somehow makes extra time and space to make everybody feel like their piece in this is crucial and that he's available.

"He's so talented and so surprising and thoughtful with his approach. He's meticulous. He works harder than most people I know."

And Caitriona added: "It was so inspiring watching that, you know, and he doesn't let it go, like, not in a bad way, in this really beautiful way.

"He would finish an incredibly long day on set where he's in every scene, he's got such heavy loads of dialogue.

"He was going home, he was watching the rushes, he was coming in the next day, I could hear his conversations with James [Hawes] being like, 'Okay, we're still in this location, maybe we just need to get this one moment. I'd really love another crack at that.'"

'The Amateur' sees Rami's CIA decoder alter ego Charlie Heller use his intelligence on a "dangerous trek across the globe" to pin down terrorists who were responsible for an attack in London that claimed the life of his wife Sarah Heller, played by Rachel.

And Caitriona, who plays Inquiline Davies, liked the "beautiful shift" towards the end of the film that highlights the "very important moral difference" between revenge and justice.

She said: "I think that very often we confuse revenge for justice. I think justice is something that when something terrible happens, we all want it.

"I think it's necessary. It's a necessary part of our process in being able to overcome trauma or step through trauma, but I think revenge is ... it only inflicts more pain.

"You have this real beautiful shift, I think, toward the end of the film where he's perhaps realising that there is a very important moral difference between the two."