Christmas Special 1974 (a.k.a. A Perfect Christmas) - S8-E7
Continuity mistake: Harold suggests to Albert that they spend Christmas abroad. Albert has not been abroad since his military service in the First World War, so Harold obtains Albert an up-to-date, modern passport. The fact that Harold has an old passport, but Albert has a newly issued passport is absolutely essential to the story. This contradicts two previous episodes of Steptoe And Son. In Pilgrim's Progress (S4-E7) Albert wanted to re-visit the First World War battlefields: Albert and Harold went to an airport and boarded a plane for France. In A Winter's Tale (S5-E2) Harold bought a ticket for a ski-ing holiday in Switzerland. He had an accident and could not go, so Albert went instead. (Albert would have needed a passport for both trips.) This also contradicts the 1972 Steptoe And Son cinema film, in which Harold married, and took both his new bride and Albert on his honeymoon to Spain.