We all belong to several kinds of community and that belonging plays an important part in the make up of our identity. In the last of the series, Lenny criss-crosses Britain to discover how humour can draw boundaries between some communities - and how it can also break those boundaries down. He begins at the last surviving coal mine in Wales. Tower Colliery has survived strikes and tragic loss of life to emerge today as a profit-making concern, owned by the miners themselves. Joining one shift, Lenny is very much the outsider in a masculine world, seeing if he can get accepted into this "band of brothers" through his sense of humour, and discovering exactly what makes this such a special community. Lenny then catches a ferry to southern Ireland and talks to truck drivers who've worked together for 20 years. Their community of workers is under threat because of the increasingly mobile nature of the workforce. His investigation into the changing nature of this 'floating community' is cut short by a Force 10 storm. In Wexford, Lenny goes in search of the famous Irish 'craic', meeting the clientele of Mary's Bar. The lessons they give Lenny in lilting gives him a unique new perspective on life. Then it's off to Belfast to reveal how his family became experts on 'The Troubles' thanks to the news reports from their hero, Trevor McDonald. Lenny checks in to the Europa Hotel and talks to the manager about how times have changed since it was once one of the most bombed hotels in the world. Lenny takes a trip with Billy the taxi driver to sign his name on one of the Peace Walls. Can humour thrive in the face of communities divided by politics and religion? To find out, Lenny joins a group of Irish comedians as they warm up for the satirical TV show – 'The Blame Game'.