You'll probably mention Neighbours in the second sentence. In America they don't mention it at all.” Well, at least that early namecheck gets Alan Dale's prediction out of the way. The Kiwi who made his name as Jim Robinson in the series has spent almost a decade in the US reinventing himself only for a Brit to dredge up his soapy past.

Dale, 60 and very fit, looks as though he could swing a mean right hook if the mood takes him, but after a pause he laughs off his history. As one can when one is successful. In recent years he has pitched up in The O.C, 24, The West Wing, Lost and, most recently, as the publishing mogul Bradford Meade in Ugly Betty. He is currently ensconced in a shabby Shaftesbury Avenue rehearsal room discussing his latest challenge, taking over from Peter Davison as Spamalot's King Arthur. When a subject he is not keen on comes up, such as the aforementioned Neighbours millstone, there is a brief chill in the room, but other than that he is open and convivial company. Friendly, but with a tough underbelly. Combine that underbelly with cropped white hair, and you can see why he has a virtual monopoly on those mean boardroom desk-bashing parts.

Scouring his CV I cannot see much theatre, but Dale politely but firmly puts me right: “As a young fellow, our family used to go to a lot of theatre because telly didn't come to New Zealand until the mid-1960s. We were into amateur dramatics and eventually built our own theatre in Auckland.” Dale was also a gifted rugby player but “the acting fraternity didn't like footballers and the footballers didn't like actors”, so he was forced to choose. “I played an Indian chief in The Royal Hunt of the Sun and gave up rugby. Acting gave me the same buzz and there was the chance of a longer career.”

However, work was limited in a country with a population of only three million. With a family to support he turned his hand to everything from selling cars to real estate. It was while driving a milk float that life took a dramatic turn. “I heard a DJ make an arse of himself and walk off the radio station, so I had a shower, went to their office and said I could do better. They gave me a go and then the day I was offered an afternoon show I also got a call from the TV network where I had tried the same trick and landed my first series.”

Dale does not lack confidence, yet refuses to see it like that. “The other choice was curl up in a ball and be an unhappy milkman all my life.” He oozes can-do positivity from every muscly pore. “Churchill said, ‘Never, never, never give up' and that's my motto. I've got it on my fridge and on notepads all over my house.”

In the late 1970s he moved to Australia and made his name there. Jim Robinson moved into Neighbours in 1985 and stayed for eight years. It made Dale a star, but no fortune. He calls the people that made the show “rip-off merchants” and even if his character had not died of a heart attack - another recurring pattern - he would not be returning.

But after Ramsay Street the work dried up. By now he was on his second marriage, to the former Miss Australia Tracey Pearson, but things were not all rosy. “After I'd been out of Neighbours a few years I couldn't catch a cold. I did well with voiceovers, but I was heartbroken.” His break came on a cheap US TV movie filmed in Australia called First Daughter. “I found I could do an American accent and decided to go for the launch in August 1999. By January 2000 I was living there.”

Dale was starting again at 52. And his age was a surprising asset. “A lot of the American middle-aged faces were too familiar, I came along and people were saying ‘Who is this great new guy?' And I was cheap. After Neighbours common sense says trade down, but I thought I'd try the opposite. If you get punched in the balls by someone bigger it doesn't hurt any more than being punched in the balls by someone smaller.”

He took his restart seriously, even going to drama class. “My teacher taught me that you might want to play great roles, but truth is you will get cast as a specific type. Just work out your type. The others in the class said I was a bit Anthony Hopkins and a bit Sean Connery and that went into my head. I thought if I go for roles those guys would go for I'm more likely to get them.”

Since then Dale has carved out a niche as an alpha male. “I either play rulers of the world or the guy who kills the ruler of the world.” Last month he was a sinister scientist in Torchwood and in May he is the US Defence Secretary in the ITV drama Midnight Man. “I've also done Commerce Secretary, Vice-President and President.” Not bad for a Kiwi washed up in his forties.

And with Spamalot he has become a king, too, inheriting the crown from current monarch Davison and before him Tim Curry and Simon Russell Beale. How does it feel taking on the lead role in Eric Idle's long-running musical? “It's the singing and dancing that's the problem,” he confesses. In fact, it turns out that he is not a complete stranger to the soft-shoe shuffle, having appeared in Applause in Queensland in 1984. He is working hard to clear out the cobwebs and stamp his mark on the part. “I might do a bit more singing than Peter.”

I assumed he had come to England because of the Hollywood writers' strike, but he was ahead of the curve. “They advised me they were going to write me out of Ugly Betty and my people put out the word.” He is also in the forthcoming Indiana Jones and the Kingdom of the Crystal Skull, but if he tells me about it he would have to kill me. “The script was printed on tin foil so you couldn't photocopy it. All I can say is that I'm a good guy.”

Given that he is hot in LA isn't he taking a risk packing his bags again, albeit temporarily? His handsome lined face looks shocked. “Don't people realise the West End is Mecca? You don't shrug that off. Life's too short. And, of course, I love Python. I just wish my dad could have been alive to see me. Both my parents died a couple of years ago and they would have loved to see me on the stage in London.”

The intriguing thing is that while Dale gets lots of TV work, he usually gets killed off. Does he ask for too much money? “No, I think these shows are run by young people who take too much notice of blogs. They read that people don't like my character so write me out, but they are not supposed to if I'm the villain. They wrote me out of The O.C. and the show closed 18 months later. I'm interested to see what happens to Ugly Betty.”

Since Neighbours, however, he has toughened up. “My family is my snail shell. I go home and shut the door and don't care if people don't like me.” At an age when others might be winding down or doing panto, Dale is busier than ever. And it is easy to see why. Vanessa Williams, who played his scheming lover in Ugly Betty, was a former Miss America. “I was leaving Miss Australia in bed at home to go to bed with Miss America,” he smirks. With work like that one hardly needs to ask what one's motivation is.

Spamalot, Palace Theatre, Shaftesbury Ave, London W1 (www.montypythonsspamalot. com 0870 8900142), ongoing

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