Johnny Depp thinks his 'Pirates Of The Caribbean' character Captain Jack Sparrow has "hit a wall".

The Hollywood hunk - who recently completed filming on the fourth instalment of the movie, 'Pirates of the Caribbean: On Stranger Tides' - doesn't believe the eccentric character will ever "find himself" in a movie because he has no further development to undertake.

He said: "I mean I honestly think this whole thing about characters and character archs and 'finding themselves' and this and that, I honestly think old Captain Jack found himself a long time ago.

"I don't think there's any more room to-he can't go any further, I think he's hit a wall as it were."

The 47-year-old star added he was delighted to work with Penelope Cruz - who was pregnant throughout the shoot - because she is a "force to be reckoned with".

He told Collider.com: "She's a serious force to be reckoned with, Penelope.

"She's really a treat, she's a heavy hitter. You can throw all kinds of stuff out there into the atmosphere and she'll Snatch up something and throw a curve ball back at you. It's very stimulating, she's someone I adore, one of my best friends, so yeah it's been great having her."

The movie - which also stars Ian McShane, Geoffrey Rush and Dame Judi Dench - is set for release on May 20.