Everyone works like crazy to get the show back on track, and we make it to Death Valley just as the sun is setting. The scene that follows - with Ellen dressed in a white suit and wrapped in copper tubing whilst pulling a Heath Robinson cart behind her sprouting silver foil pipes - is one of the most memorable of the series. Watched by some bemused German tourists and a flabbergasted National Park ranger, Ellen sets off across the desert. As the wooden wheels fall off the cart one by one, she continues dragging it across the salt playa, whilst reporting back breathlessly to Kate by walkie-talkie. Everyone - even the tourists - dissolves in hysterics. The film crews try not to laugh on camera, but the scientists and Kate are beyond help - almost unable to speak. The ranger confirms that no more bizarre sight has been seen in all his years at the park.

Other highlights from the series? The solar balloon in episode five (aerial surveyor). I was so sure that it wasn't going to work that I was strolling back to the cars telling the others that it was a failure. Then there were screams of excitement behind me, and I turned around to see the balloon rising gently into the morning sky. Miraculous camerawork from Keith caught the scene. And the water rockets in episode six - never have I heard so much insane cackling in one day.

Before we could start filming we spent hours - days even - negotiating for filming permits. The Bureau of Land Management, the National Park Service, the City of Los Angeles, the State of California, the Department of Water and Power, the Forest Service; the list went on and on. The US protects its wilderness fiercely, and the discussions are sometimes tortuous. Even though we are an "educational" programme, some organisations want to charge us as if we were making a car commercial. We have to supply lists of the plants that Ellen may need (before she knows herself), and the rocks that Iain may want to chip at. Exact locations have to be supplied weeks in advance, so I try and explain that this is a "reality" show, and our scientists have to have the freedom to act on the spur of the moment. In the end we negotiate enough flexibility to get most of what we want, but it is a long, tiring, frustrating process.

Yet that is not my main memory of filming. I remember two things above all else. First, the privilege of filming in one of the most extraordinary places on Earth. The desert - and some of the people who live there - won me over completely. Just one example; driving home at the end of each day we cruised through an endless Joshua tree "forest", with the sun setting over the mountains ahead. The majesty of the scenery was beyond words. Commuting in to the urban desert of White City in West London is something of a let-down in comparison. And the second memory is of working with a team who made this series the best fun I've had making television in a very long while. Hopefully some of the sense of excitement, fun and energy that we felt whilst we were filming has translated onto the screen.

Rough Science aims to show that science is fun and practical - it certainly felt like that when we were filming.

< Previous