Having remade The Ladykillers, the Coen brothers (they write but don’t direct) do similar injury to a fondly remembered caper movie, reheating the worst aspects of 1960s humour (the racism, the gurning, the tippy-toes mime, the whoops-there-go-my-trousers) while Cameron Diaz, Colin Firth, Alan Rickman and Tom Courtenay take the money and run.