Someone famously said that there is a sure-fire way to make a
small fortune out of racehorse ownership. First, you have to start
off with a large fortune...

I am an unashamed fan of National Hunt racing – that's the one where they go over jumps – and it has long been my dream to be among the other owners in the paddock before the race, remarking on how well my horse looks "within himself" (whatever that means), giving a last-minute pep talk to the jockey, discussing tactics with the trainer and telling anyone who'd listen that I can't see him being out of the first three.

Unfortunately, this must remain a fantasy, as I am unlikely to be in the position to say "Hasta la vista" to a big old chunk of money, as this, whichever way you look at it, is generally the lot of the racehorse owner.

In any case, I have found that you can have just as much fun and excitement when you pick a horse out of the chorus line and follow his progress. This I did six years ago with Kauto Star, and whatever the odds may have said, he was always my favourite. The white blaze down his nose is as familiar to me as any of the physical features of my friends and family.

In Kauto, I had made an emotional rather than financial investment, but I would not have not been more thrilled with his five victories in the King George chase, or his two Cheltenham Gold Cup triumphs, had I in fact been his owner. Plus, I was one step removed from that heart-stopping terror which must strike an owner every time his or her horse falls.

National Hunt racing is a dangerous sport, and not just for the horses. There are enough human casualties at the end of four days of the Cheltenham Festival to warrant a temporary field hospital, but it still represents one of the highlights of my year.

I haven't missed a Festival meeting for almost two decades, and wasn't even deterred by being shot at one year. It's true: we were sitting in a traffic jam near the course and someone with an air rifle (on a grassy knoll, perhaps) took a potshot at us, shattering a window.

And this year, I have an even more pressing reason to attend. Because if you can't afford to have your own horse, it's as well to know someone who can. My dear friend, the actor James Nesbitt, has a quarter-share in a horse called Riverside Theatre, which, after his victory at Ascot on Saturday, goes to Cheltenham next month with a favourite's chance of winning.

Riverside Theatre, named after the auditorium in Coleraine, Northern Ireland, where James made his acting debut at 13 as the Artful Dodger, looked exceptional in winning on Saturday, particularly after fracturing a pelvis almost a year ago.

For that entire time, James and his friends had been paying vets' bills and wondering whether their horse would ever make it back to the track again. In this world, such is the fine margin between triumph and disaster.

It was fitting that James – a man not prone to reticence – and his colleagues celebrated so enthusiastically on Saturday, a double measure of joy, with a dash of relief.