Treasure Island on Sky 1 HD"Pirates know how to have fun."

Describe your Squire Trelawney -

Well he's nothing like he is in the book. In this he's a rich kid born with a silver spoon in his mouth whose father was quite overbearing. He just really wants to prove himself and he gets this opportunity to go and have an adventure and hunt down the treasure. He wants to be seen as a sort of the captain of the ship, an adventurous type, but actually he's one of those guys who's 'all the gear and no idea'. He sees himself as in charge and is constantly fighting with Smollett and wants respect - but doesn't really have it from anyone. It's also his fault that Silver and the pirates are on the ship in the first place – he recruits them.

So in some ways a bit of a try hard?

Well he hasn't had to make his own wealth, but he's always tried to prove himself in his father's eyes. I got the impression that he had a father who did a lot of things; his father was a very well respected officer in His Majesty's Navy. He's trying to live up to that and find his way in the world. This is his opportunity - but he's just not capable. Even though he's very good at sword fighting.

What happens to him?

On the voyage out there he realises that nobody likes him and it all starts to go horribly wrong. Somebody attacks him and he has them keel-hauled and killed, then there is a mutiny, he loses everything, including the map, he ends up on the island with a bunch of people who don't like him and gradually he just gets more and more obsessed with the treasure. He gets gold fever and just goes a bit mad.

Your character is in plenty of sword fights. Did you take any blows?

Yes, I got hit on the finger by Geoff Bell I think it was. But no, nothing serious. Some of the others have had nasty things happen to them that they'll try to lay on me but I refuse to take the blame. The worst case scenario was 50/50. I am not this manic person who just goes slashing away!

What is your costume like and what's it been like wearing it in Dublin and then Puerto Rico?

It's wool breeches, frilly shirts, waistcoats and wool overcoats. It looks great – he's sort of based himself on an Admiral in the Navy - but it's not comfortable. In Dublin my costume was not warm enough, so I was freezing. And in Puerto Rico it was too warm so I was boiling. I had no winning situation. The pirates at least were cool in Puerto Rico because they were in linens and torn shirts.

Has he got the tri-cornered hat going on?

I wouldn't wear the hat. Wardrobe made me try it on. And I tried it on for about two seconds and said 'no way!' I had the sideburns though. I had an option to have them stuck on, but I thought in the heat and then also in the cold it would be a pain so I'd rather have my own. Some actors' were fake. Mine were real.

What did you make of the schooner, the Earl of Pembroke?

It was fantastic. But there's not a lot of room on board to film, I have to say - you can go a bit stir crazy. I am glad to be off of it now. It is such a confined space. At one point they had two tug boats with ropes attached to the mast so that before we started filming they would pulled the boat over to one side so it would start rocking. There were a couple of nights when I lay in bed and I did feel like I was still rocking.

How was five weeks on Puerto Rico with a large male cast?

I am aware that I had sort of one of those special jobs that you never forget. But it was full-on - both on set and off. It was a bunch of lads in the Caribbean with days off - that's a recipe for disaster. And there were quite a lot of pirates on that ship. Pirates know how to have fun.

How was working with Donald Sutherland?

It was amazing. Just to shake his hand. He worked with my father [Welsh actor Peter Penry-Jones] back in the sixties and he immediately realised who I was - he had rung to check. When he found out my father had died he just gave me a massive hug. It was very emotional actually. To be hugged by Donald Sutherland on your first meeting was amazing. And then there's Elijah Wood. When you have two people like that in something it just... everyone just suddenly treats it differently. The thought is that maybe we're in something really quite incredible, rather than just the usual Brit TV faces.

Did you read the book as a child?

I have read the book. I didn't read it again because I knew Trelawney was completely different to what I thought. It was just going to freak me out that I was playing some 65-year-old buffoon; I'd rather just ignore that and make up my own character.