Isla Fisher nearly 'drowned' whilst filming terrifying stunt that almost went horribly wrong

Isla Fisher opened up about the terrifying situation which saw her nearly 'drown' while filming a stunt that almost went horribly wrong.

The 48-year-old Aussie actress starred in the hit thriller-crime flick Now You See Me back in 2013 alongside a star-studded cast featuring Jesse Eisenberg, Mark Ruffalo, Morgan Freeman, Dave Franco, Michael Caine, and Woody Harrelson.

Fisher took on the role of one of the 'Four Horsemen', Henley Reeves, which also included Daniel Atlas (Eisenberg), Merritt McKinney (Harrelson), and Jack Wilder (Franco).

In the opening scene of the movie, we see the gang wow a crowd of spectators with their magic show which ended in Henley's performance seeing her have just one minute to make her Houdini-style escape from an underwater tank before a load of piranhas were dumped into the tank.

While filming, however, the production crew didn't clock Fisher was actually suffocating in the tank, putting the situation down to her stellar acting performance instead of the life-threatening ordeal it was.

Take a look at the scene below, but brace yourself, it's pretty stressful:

Fisher opened up about why she wanted to film the stunt herself - something which clearly could have had some pretty dire consequences.

Speaking to Cosmopolitan at the time of Now You See Me's release, she shared: "I don't see myself as particularly brave.

"If something terrifies me, I am going to do it."

The Confessions of a Shopaholic star continued: "The director [Louis Leterrier] said to me, 'Wow. I've worked with so many actors on big action movies, and you're the only one who's done all their own stunts'.

"I said, 'I didn't know I had a choice'. I thought you just had to get on with it. It's the Australian way!''

Isla Fisher opened up about the 'terrifying' experience on the set of Now You See Me (Lionsgate)

The scene in question saw Fisher's character finally manage to release herself from the shackles before making the terrifying epiphany that her chains were trapped between the grates at the bottom of the tank.

And it was during this moment when one of her chains actually became trapped for real, prompting her to start frantically banging on the tank walls to try and alert the crew who were none the wiser, thinking she was just acting out the fear.

"They had a guy who was off camera, but he was a long way away with a can of oxygen... by the time I realised I couldn't get up and beckoned for him, I realised that I had run out of air," she recalled.

The actress revealed she spent two months preparing for the scene (Steve Granitz / Contributor / Getty Images)

In a separate interview, Fisher revealed she spent a whole two months preparing for the tank scene.

She said: "I was just practicing holding my breath and getting comfortable with the handcuffs. It still didn't stop me from being actually stuck underwater.

"I couldn't breathe or get up for air, which was a little hairy," she said. "A lot of the time I was in the tank, it was just like white noise. I couldn't hear anyone."

Fisher added: "The adrenaline of being chained underwater meant that I had less oxygen in my lungs, I ran out of air quicker and panicked slightly more.

"I got up to three minutes underwater - that's what Louis, the director, told me he saw when he was in the editing room. It was terrifying, but I really enjoyed it."