Ruby Rose had to be rescued by a team of safety divers while shooting 'The Meg'.
The 32-year-old actress portrays scientist Jaxx in the upcoming shark adventure movie, and though everyone working on the film was very impressed with the way she was able to swim with her clothes on, they didn't realise at first that her garments had caused her to get into difficulty.
She explained: "It was a scene in which I'm in the water and have to swim back to a boat.
"My clothing, including a layer of thermals to help with the cold, made it really difficult to swim ... everyone loved how it looked and thought I was doing a great job, they didn't realise my shoes had filled up with water and were making me sink to the bottom of the tank we were shooting in.
"The next thing I know, safety divers were grabbing me.
"I drank a lot of tank water, which I have a feeling is not particularly good for you."
While lead star Jason Statham used to be a competitive diver, all the cast had to go through intensive water training ahead of filming.
Rainn Wilson told SciFiNow magazine: "We had to swim through a hoop, participate in swim relay races, pull ourselves out of the water and climb various ropes and ladders in the water.
"It was a great, but brutal, workout that gave us the skills and stamina to be comfortable in the water for the filming."
But the actor admitted the novelty of shooting in water quickly wore off.
He said: "When everyone begins the day, they're saying, 'Woo, this is great, we're on a boat! We've got sandwiches!'
"Then after about four or five hours of filming, we're thinking, 'OK, I'm ready to go in.'
"Fortunately, we weren't on the high seas and didn't experience big waves. We were in harbours and bays. No one got sea sick."
Tagged in Ruby Rose