Johnny Depp has reinvented himself through the Pirates of the Caribbean movies. When the first one sailed into cinemas eight years ago he ruefully reflected that he had never knowingly starred in a hit movie.

Now, three films later, the actor has led this franchise to box office glory and made Captain Jack Sparrow a favourite for kids and grown-ups alike. This may be in part because Jack is like a naughty child himself (albeit one with distinctly adult tastes), and Depp admits that the roguish pirate captain is never too far from the surface in his own life.

“All the characters I’ve played are relatively accessible,” he smiles.

“Some of them you have to work up to but others come a little easier. Having played Captain Jack four times now he arrives pretty quickly. In fact, he arrives a little too quickly. He arrives in life a lot, even when I’m dropping the kids off at school – it’s weird.”

In this latest adventure Jack embarks on a journey to find the Fountain of Youth, along with old flame Angelica (Penelope Cruz) and the fearsome pirate Blackbeard, portrayed in the film by British star Ian McShane.

“Who the hell doesn’t want to play Blackbeard?” smiles McShane devilishly, pausing long enough to reflect on the plot point that casts Angelica as Blackbeard’s long lost child.

“Is she his daughter?” McShane adds, eyebrow raised. “I don’t know, I often wondered because all the characters lie to each other all the time. So you can question it. I’d love it if you hadn’t been my daughter Penelope.”

Cue much laughter among a cast who clearly had a lot of fun making the latest film, in eye popping 3D and with all the resources a major Hollywood production could muster. Stunning locations in Hawaii and Puerto Rico were complemented by studio work in Hollywood and Pinewood Studios in the UK. Newcomer to the series Sam Claflin plays Philip, a missionary captured by Blackbeard’s men and retained as a kind of talisman against ill fortune. The 24-year-old was just 16 when the first film came out, and explains how much being a part of the series means to him.

“It’s a childhood dream,” he beams, “and I enjoyed every single moment even though I was like a deer in the headlights for the majority of it. I’ll never forget walking through this forest and thinking how incredible it was, and being told it was all manmade – even the rocks. They did a really tremendous job.”

McShane is no stranger to Hawaii, having been there many times. He cheerily describes the island of Oahu as being like “Bournemouth, with sun”, though his scenes were restricted to studio sets that look magnificently authentic on screen.

So too do scenes shot in Greenwich, which are re-fashioned in a very credible layer of 18th century filth. It is in this sequence that Jack stumbles across his father, portrayed by the man who inspired Depp’s original portrayal of the character, Rolling Stones legend Keith Richards.

“When we started out on the first Pirates film it was very simple,” Depp recalls.

“It was just like any other character, you grab bits and pieces and out comes this weird little thing you’ve created.

“I had the idea of mixing Keith Richards and Pepé Le Pew, but I was a little worried what Keith might think of that. For a good portion of the time that I was spending with Keith I was sponging as much of him as I possibly could for the character.

“When he found out what I’d been doing it could have gone either way but he was really nice about it.

“He said: ‘I had no idea, mate’ – he was very sweet. So to be able to bring him into the fold and do scenes with him – it was one of those moments where you know you’re really lucky and I’m certainly aware that I’m lucky.”

Audiences will doubtless feel pretty lucky too, as this return to form for a series that veered off course latterly will leave their timbers well and truly shivered. And they should not rule out another adventure on the far horizon for a character that Depp clearly loves to play.

“It’s just so much fun to get away with things you’re not normally allowed to get away with,” he smiles.

“To be totally irreverent, and play it as absurd as you like is a very special opportunity.”