Nick Robinson sets out to explain why UK governments keep spending more money than they take in, and why politicians find it so hard to say no. This is the first half of a two-part BBC2 series, and Robinson uses it to walk through the mechanics of the national budget: where the money comes from, where it goes, and the political pressure that pushes spending upward regardless of which party is in charge. He interviews sitting politicians and former ministers alongside ordinary voters, asking each what they expect government to pay for and what they think it should cut instead. The answers rarely line up, and Robinson uses that gap to show how promises made at election time turn into the budget fights that follow. The film stays grounded in real figures and real departments rather than abstract economic theory, treating the spending problem as a political one first.