Daniel Radcliffe's new movie started life as "a joke".

Daniel Radcliffe

Daniel Radcliffe

The 27-year-old actor portrays a flatulent corpse opposite Paul Dano as a suicidal man in 'Swiss Army Man' and he thinks the finished movie is more "beautiful and poignant" than anyone would have guessed from the quirky subject matter.

He said: "It started as a joke. The directors said, 'Wouldn't it be funny if someone used a dead body as a fart-powered jet ski?' And they started writing around that.

"They make it utterly beautiful and more poignant than it has a right to be."

Despite portraying a dead body, Daniel admitted he found it very easy to connect with his character in the film.

He told Metro newspaper: "I relate to his general cheerfulness, his ability to see the best in everything."

Asked if that means he relates to a flatulent corpse more than most of his other characters, he added: "Yeah! You can definitely print that."

After finding fame as Harry Potter, Daniel has since undertaken a number of diverse roles, including an undercover FBI agent who infiltrates a racist gang in upcoming 'Imperium', poet Allan Ginsberg in 'Kill Your Darlings' and a haunted lawyer in 'The Woman in Black'.

And the British actor admits he loves to "challenge" himself with his career.

He said: "I have the most fun switching it up and trying to find challenging things to do.

"We're very lucky as actors, it is one of the few jobs where the harder it gets, the more fun it gets.

"The easiest shots in the world are shots where you are opening and closing a drawer - that would be an easy day but it wouldn't be a fun or interesting day.

"When there's a scene that's slightly problematic and you have to work to get it right and you do get it right, that's the most exciting thing that can happen."