I just want to goooooo,” Ewan McGregor moans, sitting astride his bike, in the first episode of Long Way Down. He is eager to start his journey: Africa, from top to bottom, by motorcycle, starting in Tunisia.

Alas, however, the caption that has just melted from the screen – “Five Months Before Departure Day” – suggests that McGregor will not be gooooooing any time soon. Indeed, McGregor is sitting in a cavernous garage-cum-office in West London, where two beautiful PAs are doing 12-hour shifts trying to sort out visas, inoculations, routes, filming permits and the special, customised leather bike jackets from Italy. No one just goooooes, these days.

Gone are the days when Shackleton just put on an extra jumper, packed a fruit-cake, and sat on his tobacco to defrost it whenever necessary.

Of course, even in this era of extreme bureaucracy and psychometric passport blether, there are ways in which one can make it easier for oneself. Deciding not, after all, to have commissioned two SUVs covered in “Long Way Down” lettering, “Long Way Down” fleeces, or the special, turquoise-coloured Belstaff leather jumpsuit might have sped things up a trifle. Indeed, given that McGregor has done this kind of thing before – in 2004, he did London to New York, via Russia – he should know exactly how much money, effort and artifice it takes for a wealthy celebrity with a penchant for adrenalin sports to “just gooooo”.

All of the first episode is taken up with trying to arrange the trip. As the hour rolls on, it’s hard not to feel increasingly bemused about what your response, as a viewer, is supposed to be to the whole thing. Are we meant to admire McGregor’s derring-do? He’s got GPS, a 24-hour doctor and two branded vans full of spare tyres. Feel all warm and fuzzy about the charity aspect? Well, McGregor went three-quarters of the way around the world on his last trip, and raised £100,000 – an absolutely piffling amount, really, compared with how much the trip would have cost. There’s no getting around it – this isn’t, really, either an adventure or a charity endeavour. It’s just the most famous holiday of 2007.

On top of all of this, there is the considerable consideration of the actor’s long-term motorcycle buddie, and companion on this trip, Charley Boorman.

To be both blunt but also, I feel, totally fair, Boorman comes across as a copper-bottomed, ocean-going, 24-carat prick. The unsuccessful actor son of director John Deliverance Boorman, Charley is the kind of spoilt, charmless boor whose self-satisfied bull-honking floats down from first class on transatlantic flights, and actually makes you glad to be poor. In the first episode alone, Boorman departs on his epic journey despite his wife being in hospital with pneumonia and a collapsed lung; is questioned by four policemen at Gatwick after telling an air stewardess that he has a bomb; and cuts up rough when McGregor’s wife – who is, let us not forget, left at home with the kids for three months while her husband burns rubber in the Dark Continent – says she wants to join the trip for just ten days.

“I want to protect the experience, and keep it real,” Boorman says, sulkily, standing next to his branded SUV, being filmed by a TV crew.

In the second episode, his major contribution is lying in a field in France, lighting his own farts.

It’s left to the oddly innocent McGregor to try to lend the expedition any sense of purpose or joy. That he does is all credit to his sap-rising exuberance, still-startling handsomeness and renegade-prince charisma. But Boorman – ugh, Boorman. You can only hope he gets raped by a lion. In a bad way.

The last ever – ever – episode of The Sopranos. Obviously I can’t say anything at all about it, as it would a) give away the ending to millions of eagerly waiting fans, and b) I’ve only ever watched two episodes, so I don’t have a clue what’s going on. I think I can safely say that the ending is a little “mysterious”, however. One – admittedly quite nutso – fansite has suggested that what actually “happens” in the last scene is that the viewer is murdered.Or “moidoired”, as the case may be. Respect to any show in which you’re not sure if you’re alive when the final credits roll.

Long Way Down, Sun, BBC Two, 9pm; The Sopranos, Sun, E4, 10.30pm

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