In 1984 a BBC documentary crew followed Karen and Marc Adams-Jones from Porthcawl through the first year of their marriage. The resulting series, The Marriage, was an enormous hit, attracting over 14 million viewers. Karen and Marc became overnight celebrities, tabloids ran kiss 'n' tells, the series theme tune hit the charts and Karen and Marc even appeared as puppets on Spitting Image. The Marriage was one of the earliest fly-on-the-wall documentaries and it ended on an ominous note. After a headline-grabbing episode in which Marc deceives Karen by going on a rugby tour with an ex-girlfriend, no one expected the marriage to last five minutes, let alone twenty-five years. This year, however, the cameras have returned to Karen and Marc's life and find them still very much together. In the build up to their silver wedding anniversary party - in which the couple try and reunite as many of the original wedding guests as possible - this film catches up with Karen and Marc and the developments that have taken place in their lives, and the lives of those around them, over the past 25 years. Mixing gloriously nostalgic 1980's film archive from the original series with contemporary footage, the film tells the story of one marriage and how it has survived. Through the prism of one family and one marriage, the film also explores bigger changes that have taken place in Britain in our attitudes towards love, sex and marriage over the past quarter of a century. In doing so, The Marraige - 25 Years On reveals just how much we have all changed since 1984.