James Franco thinks improvisation makes a movie "more alive".

The actor stars alongside Danny McBride, Charles Dance and Zooey Deschanel in fantasy comic-adventure 'Your Highness' and is convinced the fact not all of their dialogue was scripted has made it a better film.

He said: "When you have a movie where you improvise during every scene, it's not just about finding funny lines. It does something to the actors because you're more aware. You don't know what's coming next so you don't get lulled into a way of doing the scene the same way one time after another.

"So you're much more aware and it does something to the behaviour. It makes it more immediate and makes it more alive."

In the movie, James and Danny star as brothers Thadeous and Fabious, who go on a daring mission to rescue the latter's fiancee before their kingdom collapses into chaos and James believes the comic element to the film saved it from becoming "cheesy".

He said: "Somebody said to me we might have ruined this genre for anyone that wants to treat it seriously, because it really is hard to make an earnest fantasy film. It is hard to just put on all that gear and I think people think of heroes in a different way now.

"Because this had a comedic element to it, it's like you can get away with that. So actually, I tried to play the character pretty earnestly. Because it's a comedy, we can get away with a lot of the cheesiness that maybe can hurt a film that's completely earnest. Because we get away with it, then you can actually address some of the real feelings and real dynamics between brothers and jealousy and feelings.

"If it was not a comedy, it would probably just be boring or cheesy."