Harrison Ford is baffled by his reputation for being gruff because he's actually very "silly" and "goofy" in real life

He told Vanity Fair magazine: "I always enjoyed humour. I loved jokes. I loved the construction of jokes. My father was a joke teller. The wordsmithing and the ideas that lay behind a joke have always interested me.

"When I was thinking about becoming an actor, I was ambitious for both kinds of work-serious drama and comedy. I found myself doing both and not really distinguishing much between them. I think I think with the same actor's head about a joke as I do about a serious or emotional scene."

Ford went on to insist he's a very different person when he's not working. He added: "I'm a silly person ... I don't need any encouragement [to be silly]. I'm really quite goofy all on my own.

"But when I'm in the company of other people that I know to be goofy, there's a certain relaxation of the rules. I like to have fun. I like to be around people that are having fun. I don't like to get too serious."

Ford has been married to actress Calista Flockhart since 2010 and she recently revealed the couple often pull pranks on one another - but she usususally starts it.

She told the New York Times newspaper: "I'm called the 'Scare Monster' in my house because I hide behind every corner.

"And so Harrison will walk in, and then I'll go, 'Raaah!' And he'll go, 'W-uy-aah!' And then I die laughing.

"I'll put a plastic spider inside his big ice cubes in the tray, and then he'll drink it. But then I'll go to bed two weeks later, and he's out of town in Jackson, and I'll take the covers down and there's this little rubber scorpion. It's fun."