Smash hit

But this time? “I thought that another Star Wars had broken out,” he reflects grimly. “The worst thing about the internet is that anything and everything is up for grabs. How can that be, when I limit my public conversations to about once every couple of years? Any kind of rubbish goes on the internet and it can have a f***ing life of its own.”

The complexities of the internet figure heavily in Firewall. Ford plays Jack Stanfield, a computer-security specialist, who has built systems to protect a large bank from hackers. But a supposedly respectable banker, played menacingly by the British actor Paul Bettany, has been studying his system. When Bettany’s ruthless character masterminds the kidnap of Stanfield’s architect wife (played by Virginia Madsen) and children, he tries to use him to set up the theft of $100m. As with many of Ford’s action movies, he plays the ordinary guy caught up in an extraordinary situation.

How far would Ford go to get his own family back? “I have no idea,” he says. “No one really knows how far they will go. My character is compelled to act outside his normal behaviour, using whatever methods he can.”

Those methods proved a tad strong for an admiring 35-year-old Bettany. The latter told me earlier: “I wanted the stunt guys to do the stunts — until Harrison Ford said he wanted to do his own, the bastard. He’s 63, for God’s sake.” He related how he threw Ford through a window on seven consecutive takes — “He’s built like a rock” — and how, each time, Ford got up and helped the set-builders to reconstruct the window before filming yet another. “He had me beaten for sheer energy,” Bettany conceded.

But is Ford still trying to prove a point, when he no longer has to? There has been much talk of a fourth Indiana Jones film, 17 years after the last, with Steven Spielberg directing. If that happens, can we really expect a man who is 64 in July to deliver the action with credibility? Ford is having none of it. “It is not a matter of being fit,” he says. “I don’t even work out. What counts is knowing what you can do to make it look believable. I only helped to rebuild that window because I designed it in the first place. I made sure it was built in such a way that I would not be hurt.”

Such authenticity was not a factor when it came to his character’s computer knowledge. “I’d never consider internet banking,” he says. “I don’t even know what bank my money is in.” Or how much he’s got, I ask? “I don’t want to know. All I want to know is whether there is some to spend.” Has he ever had to make cutbacks? “I am relatively frugal, considering the circumstances,” he says. “I do not live terribly large, apart from the aeroplane.” And did he ever think that time was running out to spend it? “I don’t have a really big plan to get rid of it — yet,” he replies. “It is a big question when you have a lot of money, how much you leave behind to confuse your heirs. Money you do not earn can be very dangerous. But they do inheritance tax in America, just like in Britain. So I have to do something about it. I suppose I am still looking forward so much.”

And, looking forward, what if anyone were to say he is too old to deliver Indiana? “I would invite them to step outside,” he says with a grim smile. “More seriously, I’d say, ‘Take a look at Firewall.’ I think I am still up to the job.”

Firewall is released on March 31