On The Buses Boxing Day Social Christmas Episode 1971

It's Boxing Day and Arthur's mother has come to stay, along with his sister Linda,who throws herself at all the men, including Jack. The two families go to the bus company's dance where Arthur warns Jack to keep away from Linda but is himself the object of desire for conductress Beryl, leading to Olive causing a scene. Later, as Blakey shows Arthur's mother around the depot, they catch Stan and Linda in a compromising position.