Penelope Cruz says the hardest thing about her Pirates role was not all the swashbuckling and sword fighting and sailing the high seas.
It was not even the added rigour of being a pregnant pirate as she filmed her scenes last summer for Pirates Of The Caribbean: On Stranger Tides while carrying her first child, a son with husband Javier Bardem born early this year.
The actress said her toughest job on the fourth Pirates flick, overseen by her Nine director Rob Marshall, was staying in character opposite Johnny Depp as woozy buccaneer Jack Sparrow.
"To keep a straight face sometimes with Johnny in some of the more dramatic scenes," Penelope said. "I would look at him doing the things he does as Jack Sparrow, and Rob had to cut so many takes with Johnny or me, because we could not control ourselves. He would provoke me and always make me laugh.
"It was harder than the swordfights, for sure."
Penelope, 37, jumped at the chance to take the role of Angelica, Sparrow's embittered former lover, before even reading the script.
"Then I read it, and I discovered it was this manipulative pirate and a character so full of colours and contrasts and contradictions," she said.
"I was very happy with the material when I read it. I thought there were a lot of possibilities. It's so much fun to play a liar, because I'm not a good liar in life."
The pregnant actress was given an elastic corset to move more freely, and her outfits were constantly being altered.
"I just had a new fitting every three weeks," she said. "We kept having fittings, but they were very, very kind to do it."