Overview: William Woollard and Sue Baker present the first of a new series from Europe’s biggest and brightest motor show at Frankfurt. On the road, Chris Goffey has been driving the new Citroën XM — will it live up to the French company’s reputation for innovation and comfort? And there’s a road test of Mercedes’s new SL sports car, soon to be launched in Britain. But are German motorists’ attitudes to the car changing? Jeremy Clarkson reports on how the nation with more cars than any other in Europe is coming to terms with congestion and pollution.