Anyone who has struggled with Eurostar's internet booking service, braved the Northern line to get to Waterloo and weaved through queues to catch the high-speed rail link from London to Paris knows you need at least one more thing long before you reach the platform: a valid ticket.
So when I watched the chief protagonist in The Constant Gardener – the new film that attacks "big pharma" drug companies' practices in Africa - being accompanied by his non-travelling friend right to the doors of the train, my own personal electrocardiograph was already spiking at the thought of inaccuracies to follow. It might be a trivial error but it is the sort that makes you wonder what else could be questionable in a Hollywood film based on a John Le Carre novel that turns the companies that are supposed to be advancing human health into the principal villains.
By the time in the film when one villain mutters in repentance that "big pharmaceuticals are up there with arms dealers", any drugs company executives still watching will be reaching for their blood pressure pills.
There is no doubt that drugs companies have indulged in some dubious ethical practices over the years. Providing cheap medicines to the poor has never been part of their core mission. But after a remarkable few months in which more than half a dozen books have been published on the evils of the sector, with titles such as The Big Fix, On The Take and Selling Sickness, you have to wonder whether the mercury is rising a little too high. Public reactions to The Constant Gardener, and a likely Michael Moore film in the months ahead, almost guarantee that pharmaceutical executives will be self-prescribing more anti-depressants.
We now all know that Vioxx, Merck's over-sold painkiller withdrawn last year, may have contributed to the death by heart attack of significant numbers of patients, although scientists and lawyers will argue for years over the benefit of hindsight and the influence of other factors. Yet millions have benefited from recently launched drugs, including Herceptin for breast cancer and Exubera, the inhaled insulin treatment for diabetes. Merck and GlaxoSmithKline's vaccines could soon prevent cervical cancer. The antiviral Tamiflu may save many lives in the event of an avian flu pandemic.
Even Viagra, dubbed a "lifestyle" drug and sometimes used to whip the industry for not focusing on more important illnesses, was originally tested as a heart drug before researchers discovered it had an unanticipated effect on blood flows elsewhere in the male body. Viagra fuelled the questionable industry practice of advertising to the general public. As one executive joked recently, he knew that the focus on "direct to consumer advertising" had gone awry when his young nephew came into the room after watching television and asked: "Uncle, what exactly is reptile dysfunction?"
Perhaps the companies' biggest problem is that, while they are profit-making entities, they produce drugs that are widely perceived as a public right. That creates a contradiction in many minds, and a convenient whipping-boy, whereas these are responsibilities that society should share. To improve their image, companies should certainly do more to focus on innovative drugs in important therapeutic areas - even though they face enormous scientific obstacles, have to run costly clinical trials and are dependent on healthcare systems that help determine drug prices, purchasing and distribution. In the developing world, the companies continue to make absurdly inflated claims about the donation of hundreds of millions of dollars of drugs valued at western prices that they would not otherwise sell. Making their medicines available more cheaply in lower income markets would make economic as well as ethical sense.
Yet the premise in The Constant Gardener - that evil western pharma giants are covering up lethal side-effects in clinical tests on Africans as they prepare a global blockbuster tuberculosis treatment - pushes the limits of credibility. If a new generation of TB drugs really had the potential to sell so well, companies would be doing a lot more to find them. And there would be little advantage in launching them after trials that showed they killed African patients, given the litigation that would follow as patients in the west died too. In reality, the TB Alliance, a public-private partnership, is about to unveil the latest in a series of collaborations with drugs companies that could offer hope for significantly better and affordable treatments within five years, despite few prospects of profit.
If the drugs companies have sinned by neglect, they at least sell products that improve human health. That hardly puts them on the level of tobacco companies, let alone arms dealers. Let us hope that if The Constant Gardener does become a blockbuster, it not only stirs a public debate and motivates the drugs companies to do more, but pushes governments and others to reflect on their respective roles. Maybe even the film's backers might make a little financial contribution to improved African healthcare.