If you want to imagine, look up. Ten minutes by car from Watford Junction station stand nine film studio stages, cathedrals to creativity: the brand-new Leavesden Studios. Built in 18 months, they dwarf the visitor paying homage in an ersatz Hollywood golf buggy. The 81-hectare studio lot they are part of is the new British home of Warner Bros, a facility so large that it is one-and-a-half times the size of the company's studios in Burbank, Los Angeles.
Josh Berger, the president and managing director of Warner Bros in the UK, Ireland and Spain, is the man wielding the metaphorical hard-hat and shovel at a site 15 miles north of London that officially opens for bookings on Monday. Now a division of Time Warner, Warner Bros has a connection with the UK that dates back to the shooting of pictures at Teddington from the late 1920s onwards – but took off in its modern form once the studio obtained the rights to JK Rowling's Harry Potter series in 1998 and agreed to her request that the books be filmed here.
The 45-year-old American, who has been in Britain for 16 years, fits the stereotypical image of a Hollywood producer, with flattery and bonhomie on tap; he is a not unfamiliar figure at the Ivy, always eager to acknowledge the presence of others in the London restaurant popular with media suits and celebrities.
During his tenure, the 94-year-old US company's British presence has grown. Warner Bros owns Waterloo Road producer Shed Media (a group including Wall to Wall and Twenty Twenty Television), has sniffed around Big Brother's maker, Endemol, and owns two British video games developers. Even last year, with the Watford operation yet to open, it part-shot seven movies here, including scenes for The Dark Knight Rises.
The "irony", says Berger, is that it took eight Potter films and a total box office gross of $7.7bn for Warner Bros to buy Leavesden Studios, where the films were shot, in November 2010. The Hollywood studio paid the property group MEPC £22m before rebuilding the site. "How often have you seen over £100m invested in the UK in a time of recession?" Berger asks; the facility also has an underwater stage, three smaller TV studios and "one of the most extensive back lots in Europe" for outdoor scenes.
Leavesden was once a Rolls-Royce engine factory, but films, Berger reckons, are the new manufacturing: "We're employing 400+ people on site, plus an estimated 300-500 per production. You can see how this rolls out into the community. Go and talk to the local taxi company: they know when we're busy, when we're quiet." Keeping a site with the capacity to film two blockbusters at once busy will be Warner Bros' challenge. It helps that next door is the Warner Bros Studio Tour – a £28-a-ticket celebration of the movie versions of the Harry Potter novels that showcases the films' sets, designs and techniques, from prosthetics to green screens. Able to cope with up to 5,000 visitors daily, this is "definitely not" a theme park – and of course the rights to create Harry Potter theme parks have been licensed to Universal Studios, a rival to Warner Bros. Visitors to the US theme park will get "a noisy American" experience, with "claptrap", says Berger, noting that "Harry Potter fans are very passionate people. The experience here is a emotional one, to be in the actual Great Hall, to be in Diagon Alley. It's more of a British experience."
Yet he insists that the visitor centre is not intended to offset the risk of the studio business, arguing these were "two separate investment decisions". He praises the tax break regime for British films set up by Gordon Brown, a rebate worth 16% to Warner Bros on large productions, for providing a "great service" to companies such as his. "Now it really goes to film-makers, the tax credits go to production companies who shoot here, and it creates an environment that makes it favourable to continue to invest," he adds.
Even though it faces competition from Pinewood Studios, 17 miles away down the M25, Berger reckons the company can profit from the increase in British studio capacity. "Our business has been resilient and historically counter-cyclical," he contends optimistically. There has been a shortage of capacity in the UK – Pinewood has reported high utilisation in recent years – but it helps that Berger has a Hollywood studio behind him in his mission to fill the space.
However, his most important argument in defence of his adopted country is economic and cultural: "Look at what we've made, from Harry Potter to The King's Speech, the breadth of British cinema now, both commercially and from the creative point of view," he enthuses, pointing out that "you don't have to convince a US movie star to spend three months in London".
There is also a growing Anglo-American exchange of creative ideas to sustain future productions, and here Berger points to television, noting that "now we have planted our flag here" there are "close links between our British TV creators and our Hollywood-based TV production". A pilot of Bad Girls is being made for the US, and a second series of the UK version of Warner Bros' dating show The Bachelor will be on Channel 5 later this year, with Spencer Matthews from Made in Chelsea taking his pick of 24 women.
Asked about The Voice, which is made by Wall to Wall, Berger says "all the producers will sit down and work out how to continue to improve" in the light of the BBC1 talent show's softening ratings, a statement of the obvious that nevertheless alarms his PR department.
There is clearly interest in more Time Warner acquisitions in Europe, but he has no comment on debt-laden Endemol, for which Time Warner made an unsuccessful €1bn bid last year. Decisions about any move on ITV are taken by another Time Warner division, its channels business, Turner. So Berger has also nothing to say on this, although he points out that Turner hired the former RTL chief executive Gerhard Zeiler this year to oversee its international business. He describes Zeiler's appointment as "interesting".
Berger likes being asked whether he has been asked to apply to be BBC director general. Flippantly, I ask, isn't the pay so low it amounts to charitable work? "I'd rather do that for the Chickenshed Theatre," the north London "inclusive theatre" company that he chairs, he replies, which is his way of saying you can rule him out.
Anyway, Berger has quite enough to do. His job now is to find directors with large enough imaginations and producers with stupendous budgets to keep bosses in Burbank happy and studios in Hertfordshire busy.