Shhhh! He’s on the train. Yes, I mean Gordon Brown. It’s top-secret but it’s true. I wish I knew more but if I did I’d have to kill myself. Still I tried. My first call about this was to Downing Street, who told me they could not help in any way. I brushed this off. I am a commuter. I expect a total lack of information about anything to do with trains.

Mussolini made the trains run on time. Stalin ruled Russia from his personal train. And Gordon Brown? Well, on the very morning of his Great Train Journey he requisitioned one. Most people are content to buy a ticket; our Prime Minister had to have an entire franchise. It seemed a little excessive (and much harder for the conductor to punch a hole in).

I call Downing Street again. They refuse to tell me anything about his schedule and say that, anyway, I can’t go with him. Still, I am not fazed. I’m a commuter. I’m used to being treated with contempt. I hear he’s going north and wonder if, like Harry Potter, he will depart from platform 9¾ at King’s Cross.

Actually, having just been to PMQs to see Mr Brown on the very brink of his great journey, this may well be the case. Mr Brown seems well acquainted with fantasy numbers. At one point, as he and David Cameron fought over whether total spending is going up or down, Mr Brown announced: “Total spending will continue to rise and it will be a 0 per cent rise in 2013-14!”

The Tories, 100 per cent hysterical, guffawed. Mr Speaker, who is usually 0 per cent effective, cried: “Order! Order! The Prime Minister’s answer must be heard.” The Tories screeched louder. “That answer gets 0 per cent!” chortled David Cameron, wag that he is.

The percentages started flying like arrows on Valentine’s Day. Mr Brown accused Mr Cameron of being Mr 10 Per Cent, a reference to cuts. Mr Cameron said that was rubbish and that, anyway, the Prime Minister was Mr 13½ Per Cent.

It’s madness but good preparation for the Great Rail Journey. Train passengers (sorry, customers) are used to figures that mutate, the 20.11 that has a 0 per cent delay but never arrives because it has become, magically, the 20.41. In my experience it is quite normal to catch trains that don’t exist. The Prime Minister should feel right at home on the railways.

I ring the Downing Street press office for the fifth time. The phone rings and rings. I’m impressed. Such is their omertà that they no longer even answer the phones. The rumour is that Mr Brown may or may not have headed to Leicester. He’s going to meet “the people”. So far the main person he’s met is Nick Robinson, the political editor of the BBC. Still, it’s a start.

Here’s a theory: Mr Bean is turning back into Stalin. This week, Mr Brown gave us his National Plan. Now he’s ruling from a train. (Soon we’ll get those tractor production figures in full with 0 per cent rises all round.) Still, if his train is late, at least the company has a great excuse: the wrong sort of Prime Minister was on the line.

Times Recommends

• The bright side of this winter rain
• Story behind the picture: Snow Leopard, 2008
• Times Charity Appeal: The Place2Be