For Rosamund Pike, playing bad is good fun.

Luckily for her, her latest film, I Care a Lot, allows her to be very bad indeed. In it, Pike plays the vicious and cunning Marla Grayson, a legal conservator who runs a lucrative scam on elderly clients with her partner, Fran (Eiza Gonzalez).

Pike says the dark satire, which hits Netflix Feb. 19, presented an intriguing challenge for her as a performer. "We were trying to work out how to achieve that tonal balance where you can play somebody who's awful, but they're still fun to watch," she tells EW.

To achieve that, Pike and writer-director J. Blakeson looked to films such as The Last Seduction, starring Linda Fiorentino — Pike says she's "kind of a bitch, but she's also really watchable and fun" — and To Die For, starring Nicole Kidman, for inspiration. "When a director has commanded the tone, these things are very, very delicious," she adds. "I just knew I had to push Marla, and I wasn't trying to win any admirers with her."

Another film Pike and Blakeson found particularly helpful was Martin Scorsese's The Wolf of Wall Street, which notably features a stockbroker making a huge fortune by defrauding wealthy investors out of millions of dollars. "That sort of wonderful rise of Leonardo DiCaprio's character, where you just see them just taking everyone for a ride and you just think, 'Well, you know, it's a brilliant scheme. Yeah, I have to give it to him.' I felt a bit like that when I read Marla," Pike says. "And I haven't seen a modern film with a woman [doing that] and running it sort of like a business."

That business starts to fall apart when Marla's seemingly perfect new target (Dianne Wiest) is not who she appears to be, which pits her against a powerful gangster, played by Peter Dinklage. And it's at this point that Pike's character is forced to go from being a cunning con woman to something else entirely.

Pike is so convincing as Marla (and the similarly manipulative character of Amy Dunne in Gone Girl, which earned her a Best Actress Oscar nomination) that it almost makes one worry she's a little too good at playing bad. But Pike says not to worry. "I have nothing in common with Marla Grayson, and I think that's why it was so freeing, to be honest," she admits. "I think there are characters where you can channel bits of yourself and spin your own character flaws and character strengths sort of around the qualities that you find in a character, and with Marla there was nothing, and therefore I kind of could completely let go and sort of just be free, I suppose." In fact, she adds with a laugh, "I think the only thing we have in common is that she looks like me."

Lately, Pike has made a habit of playing courageous characters in biopics — more heroine than antihero. And while she says she loves the responsibility that comes with playing a real person such as journalist Marie Colvin (2018's A Private War) or scientist Marie Curie (2019's Radioactive) and "diving into that heart and soul," as she puts it, I Care a Lot gave her an opportunity to play someone completely without remorse.

"I think most people feel a tremendous degree of shame," Pike says. "I found it so intriguing that this was a woman — and I looked for it — and I thought, there's no shame here, there's no shame in this woman. She doesn't feel it. And she is blessed not to feel it, because it's one of the curses of being human, isn't it?"

Ultimately the British actress, who says she has a tendency to take herself too seriously, hopes audiences will be able to find the humor in Marla's ruthlessness. "You're talking about a very dark subject of people taking advantage of the most vulnerable people in our society, and yet J gives you permission to let that sink in while you're still laughing in kind of a mixture of appall and horror and delight," she says. "It's a complicated cocktail."

Complicated it may be, but it's a libation well served by this icy film. "It's obviously dealing with a very serious subject," Pike says, "but I think had it been treated as a sort of very serious drama, it might not have left you thinking about it in quite the way that this does."

Related content:

• First look: Rosamund Pike is a ruthless con artist in TIFF premiere I Care a Lot
• From Bond girl to Gone Girl, Rosamund Pike on her most memorable roles

This story originally appeared on: EW - Author:Lauren Huff