Why Rebecca Ferguson kicks 'Mission' butt

Swedish actress Rebecca Ferguson had to aim high in her first big-budget action movie, Mission: Impossible — Rogue Nation (in theaters Friday).

Ferguson, 31, had no previous gun training when she was cast as a trained sniper. Further, her mysterious agent Ilsa Faust had to hold her own against Ethan Hunt, played by superstar Tom Cruise.

But her performance in the fifth Mission film has earned critical praise (“Ferguson is perfection in the tradition of secretive movie heroines," says Deadline.com's Pete Hammond) and impressed Cruise, who says, "Rebecca makes Ilsa lethal in every way."

Here's how Ferguson hit the bull's-eye with Ilsa:

Her thighs are killer.

As a disavowed British agent, Ilsa is trained to use her best weapons in a scrap — mostly, a lethal set of crushing thighs, which director Christopher McQuarrie says were directly involved in three Mission deaths.

"That was Ilsa's speciality. I tried to bring it on as much as possible," says Ferguson. "It's an incredible move. But it took months of practice."

Baddies fell onscreen, but no actors were thigh-injured.

"I was worried about hurting somebody," says Ilsa. "But basically, the guys I jump up on are very well-trained stunt people and handled it."

Her eyes are pretty lethal, too.

"The other stuff is great, fantastic," says McQuarrie. "But Rebecca has these beautiful, expressive, somewhat-feline eyes which alternate between lovely and incredibly lethal."

In the tough spots, the gaze gets punishing, without going too far.

"The best thing about Rebecca is she makes Ilsa deadly without making her brutal," says McQuarrie.

She's born to run.

Ferguson had a custom formal dress with a dramatic cut that allowed her to break into an instant, unencumbered sprint (and also break out a thigh-kill). Even the stiletto heels were specially made for running.

But she takes her shoes off during some sprint sequences, such as running atop the slanted roof of the State Opera House in Vienna.

"Of course it could have done in high heels, but we liked the idea of kicking the heels off," says Ferguson. "Ilsa is a practical character."

She had excellent underwater training.

A key underwater Mission sequence required Cruise and Ferguson to undergo extensive breath training in order to film the scene in a single take. Ferguson learned to hold her breath for more than four minutes.

The filmmakers worked in a bathing suit scene that Ferguson didn't find even slightly gratuitous.

"The whole point is we see Ilsa practicing holding her breath in water," says Ferguson. "She would rather do that scene in a bikini than a dress, I think."

She saves Ethan Hunt's life.

It's a rare distinction to have the honor of saving the formidable Hunt, but Ilsa dives deep to pull him to safety in Rogue Nation.

"When I read that in the script, I remember thinking, 'Really?' " says Ferguson. "But Tom loved the idea of Ilsa saving Ethan."

It's all part of being Hunt's equal, and the attraction of two similar agents.

"Yes, she can kick butt. Yes, she saves Ethan's life," says Ferguson. "But basically, I love playing an agent who still has vulnerability and a soul."