When I was in England around 1990, I rode the "Pullman" train from London to Penzance and had dinner on board (I think Jis recently took this trip...). Food was ordered on the train but prepared off the train and picked up en-route. The meal was delicious!
Charlie was on it recently too. It is the Caledonian Sleeper service operated by a private franchisee, Serco for Scottish Rail Regulators which is the contracting agency, in a new franchise for 15 years. Even trying to propose such an operation in the US would be liable to be treated as blasphemy these days. C'est la vie.
BTW, it is getting brand spanking new Mark V cars, manufactured by CAF (75 cars) delivered more or less on time. They go into service in October this year.