Dom Joly: Operation Bacon nearly blew my cover at the bank

My first week of "secret" filming is over and I'm knackered. I'd forgotten just what an adrenalin rollercoaster the world of the hidden camera could be. A crew of around 20 and I descended upon the "Venice of the Cotswolds" (Bourton-on-the-Water) for three days. The inhabitants of the town were very patient with us, considering that we caused non-stop minor mayhem around them.

Through Bourton runs the River Windrush, spanned by a series of picturesque little stone bridges. Like Venice, it attracts tourists from all over the world and this, I must admit, was the main reason we chose the place. The town has a busy coach park on its edge and the hordes of visitors are funnelled through a narrow pathway until they reach the village green – where I lay in wait. It was perfect, like some tourist conveyor belt endlessly thrusting naive new flies into my web. On a coach somewhere right now are a group of confused Japanese tourists who will be taking home a very peculiar idea of what locals are like in the Cotswolds. They will also give a particularly wide berth to any vicars that they might encounter on the rest of their tour.

I normally have a rule about not filming too near home, but Bourton is just far enough away from where I live not to cause any unfortunate encounters with aggrieved locals in the supermarket. After three days of standing on street corners, however, I now feel I have probably met every single person in the place and have overheard more local gossip than is proper for any one individual.

We had only one unfortunate incident. We'd set up for a shoot around the river and a couple of our cameramen were using one of their favourite tricks – the "pramcam". This involves hiding a camera in a pram and covering it with a blanket. The cameraman then leans over the "baby" and films the action, while pretending to be a doting parent. Beautiful as this scene of fatherly devotion is, the sight of a man leaning into a pram for hours on end can cause suspicion, if not misunderstanding. This increases when you've set up outside a bank.

Concerned staff in the establishment, believing an elaborate heist was about to go down, called the police. We carried on filming unaware of any problems until Operation Bacon swung into action. Once we had explained the situation and confirmed that the pramcam operators were neither exhibitionist paedophiles nor part of a sophisticated stakeout, the police alert was reduced to a Code Amber. The force then returned to their more usual duties of keeping an eye on local celebs such as Shane Warne (a new arrival to the area on the arm of Liz Hurley).

We returned to pestering visitors, but made one change. Helping the cameraman on the pramcam we had a female member of the crew to make the family unit seem more "normal". One elderly woman wandering past a pramcam did lean in to have a look and muttered that it was a "remarkably calm little thing, doesn't make a peep". Apart from that, things seemed to work a lot better, and we were left unhindered for the rest of our time in "Venice".