In 1977 Wales had a rugby team that was second to none. When hey went to Paris to take on the French they were full of confidence.... With them went scores of Welsh supporters eager to watch their heroes beat the French on their own turf and make Wales the Grand Slam champions. It is the tale of one group of Welsh supporters that is told in Gwenlyn Parry and John Helfin's classic comedy aptly titled Grand Slam. During the course of the film we discover that 'grand slam' can mean different things to different people and that there are challenges that have to be faced off the pitch that are almost more daunting than those facing the players on the pitch. The film stars Windsor Davies as Mog Jones, Huw Griffith (the Welsh actor who won an Oscar for his role in Ben Hur) as Caradog Lloyd Evans, an undertaker by Profession, Dewi Morris as his son, Sion Probert as Maldwyn, Novello Pugh, the boutique owner, and Sharon Morgan as the accomodating French hostess. The film includes memorable rugby moments featuring legendary players Gerald Davis, JPR Williams, Gareth Edwards, Phil Bennett, Terry Cobner and Steve Fenwick. The film was directed and produced for BBC Wales by John Hefin.