For some reason it has become common to assume that ‘series’, as in television series, are a relatively recent phenomenon. In fact, as those of us slightly longer in the tooth know, they have been around for almost as long as television has been. One piece of sustained brilliant writing that I remember from my early teens was the Anglo-American production, Colditz, which was screened around 1972. It was consistently well-scripted, well-casted and well-acted and made a big impact on me and my fourteen year-old classmates. Tonight I rewatched one particularly noteworthy episode, Tweedle-Dum, which rightly won a series of awards. Michael Bryant (pictured) turned in a brilliant performance of desperation declining into mental ill health. But the script (by John Brason) leaves the viewer grappling with such questions as to whether there are frontiers between mental illness and good health and the basis on which those in authority make their diagnoses. I can’t spoil the plot. Suffice it to say that the success of Brason’s character’s ultimate escape is debatable.