updated 03/19/2014 AT 11:00 AM ET
•originally published 03/19/2014 AT 2:55 PM ET
When Kate Winslet takes a role, she really commits.
Just take her role in Divergent, for which Winslet did her own stunts – even as she was pregnant with her third child.
The 38-year-old actress’s hands-on approach was the topic of discussion at the film’s world premiere Tuesday in Los Angeles, where Divergent author Veronica Roth and the film’s director, Neil Burger, spoke out about the Winslet, who stars opposite Shailene Woodley.
“It’s pretty funny because she was pregnant when we were shooting, but she wanted to do her own stunt falls,” Roth told PEOPLE. “She did a couple. She’s you know, very careful about it, and then finally Neil Burger was like, ‘Okay I’m too nervous – you can’t do this anymore.’ ”
Added Roth, with a laugh: “She was like, you know, taking-charge lady – she powers through. It’s really impressive.”
Burger agreed that Winslet was unflinching about her role, even when she revealed to him the news that she was pregnant.
“We had to refit all of her wardrobe, but then there is a scene where she fights Shailene and she was like, you know, taking the falls and I’m like, ‘Stop, you’re pregnant.’ But she was still wanting to do it with as much action,” Burger told PEOPLE. “She’s a committed actress and she’s a committed mother, too. But she is just completely there, and you kind of just have to stop her.”
That moxie, he said, is why Winslet remains a down-to-earth but world-class actress.
“She really is, from my mind, the best actress of her generation, and there’s a reason. She’s a pro. She’s completely present.”
Divergent hits theaters Friday.
Reporting by MARIAH HAAS
Pick up the latest special issue from PEOPLE – on sale now!