Villain with secret under her coat

Kate Winslet says it's fascinating playing someone who is cunning and manipulative. Photo / AP

Playing an action-movie tyrant meant every effort had to be made to disguise Kate Winslet's baby bump.

Kate Winslet isn't known for making diva demands, but the Titanic star kept the costume and props departments on their toes on the set of her new action film, Divergent.

The Oscar-winner was five months pregnant with her son Bear Blaze when she shot the blockbuster, meaning every effort had to be made to disguise her growing baby bump.

"Behind the clipboard, behind the iPad, oh, anything to hide it," the mum-of-three recalls with a mock roll of the eyes.

"It was great, actually. Bear was there, hiding under my coat the whole time. And I suppose it won't be that long before he can see it.

"Mia and Joe [Winslet's older children, aged 13 and 10] can't see most of the films that I've been in ... and they won't for a long time, but little Bear will probably be able to see Divergent in 10 or 11 years' time."

It's been four months since Winslet - who wed third husband Ned Rocknroll in December 2012 - gave birth to Bear, but the 38-year-old isn't displaying any signs of new baby exhaustion when we meet.

What's her secret?

"It's just lovely. When you're going through it for the first time, and I was only 25 when I had Mia, you are more anxious: 'Why are they upset, what do they need?' There are just lots more questions. But now it's like, 'They're only crying because they're tired. It's fine, they're hungry, it's fine!' You just kind of know a little bit more. It's more instinctive."

In Divergent, based on the first novel from Veronica Roth's best-selling trilogy, Winslet plays a villainous leader in a dystopian Chicago, where youngsters are divided into factions based on personality traits.

"I've never really played an evil person before now," she says. "It's been fascinating for me playing someone who is quite blatantly cunning and manipulative." She describes her character, Jeanine Matthews, as a "female Hitler".

The film's themes, of fitting in and finding your identity, were "probably the biggest pull" for Winslet, and brought back memories of her own teenage years, she says - although arguably hers wasn't an average adolescence, with a stint on BBC youth series Dark Season and a big screen debut in Peter Jackson's 1994 film Heavenly Creatures both under her belt before she'd even turned 18.

"It really resonated with me, and I think that's what's going to resonate with a lot of people of that age who do go and see this film, because it's such a confusing time."

Movie profile

Who: Kate Winslet in Divergent
When: Opening at cinemas tomorrow.

- AAP