(Cover) - EN Movies - Johnny Depp insists he is a "middle-aged child".

The American actor has reprised his role as Captain Jack Sparrow in the fourth instalment of the swashbuckling Pirates of the Caribbean franchise, called On Stranger Tides.

The 47-year-old star has appeared in a host of fantasy-adventure movies including Charlie and the Chocolate Factory and Alice in Wonderland.

Johnny says his fascination with story-book films is down to the fact that he is just a big kid at heart.

"Yes. Without a doubt," he said when asked if he is an overgrown child. "I'm basically a middle-aged irreverent child. That's pretty much me."

The award-winning actor thinks it's healthy to have fun whilst at work. Films such as Pirates of the Caribbean allow him to achieve a great deal while still maintaining a joyful element.

"I think it's important to have fun within the context of work and embrace the possibilities and obstacles and challenges and things like that. Try to explore new worlds," he explained.

Johnny is a hugely successful actor in Hollywood whose films have grossed over $6 billion worldwide. He remains humble and says the success of Pirates of the Caribbean and the rest of his film career was unexpected, but "amazing" nonetheless.

"Everyday I'm amazed of where I've landed on two feet. I'm amazed I landed at all. To have landed here - I promise you that no one in Hollywood could have ever predicted it," he noted to BBC. "I consider myself to be incredibly lucky to have been given the opportunity first of all to take part in the building of the character like this, and it was a complete and utter surprise, not only to me, especially to me, but to the people behind the scenes and the Disney folk, and the Bruckheimer [Producer Jerry Bruckheimer] folk, it was a complete surprise." (C) Cover Media